@mendix/cordova-sqlite-storage
Version:
Native interface to SQLite for PhoneGap/Cordova
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Markdown
# Cordova/PhoneGap sqlite storage plugin
Native interface to sqlite in a Cordova/PhoneGap plugin for Android, iOS, macOS, and Windows 10 (UWP), with API similar to HTML5/[Web SQL API](http://www.w3.org/TR/webdatabase/).
License for Android and Windows platform versions: MIT or Apache 2.0
License for iOS/macOS platform version: MIT only
|Android Circle-CI (**full** suite)|iOS Travis-CI (partial suite)|
|-----------------------|----------------------|
|[](https://circleci.com/gh/litehelpers/Cordova-sqlite-storage)|[](https://travis-ci.org/litehelpers/Cordova-sqlite-storage)|
## About this version branch
This is the common version branch which supports the most widely used features and serves as the basis for the other versions.
<!-- END About this version branch -->
## Available for hire
The primary author and maintainer [@brodybits (Christopher J. Brody aka Chris Brody)](https://github.com/brodybits) is available for part-time contract assignments. Services available for this project include:
- Priority issue support
- Help with application code such as debugging, optimization, etc.
- Warranty and support retainers
- Priority fixes and enhancements
- Custom feature development
Other services available include:
- Front-end/back-end development
- Mentoring and training services
For more information:
- <http://litehelpers.net/>
- <sales@litehelpers.net>
<!-- END Services available -->
## A quick tour
To open a database:
```Javascript
var db = null;
document.addEventListener('deviceready', function() {
db = window.sqlitePlugin.openDatabase({name: 'demo.db', location: 'default'});
});
```
**IMPORTANT:** Like with the other Cordova plugins your application must wait for the `deviceready` event. This is especially tricky in Angular/ngCordova/Ionic controller/factory/service callbacks which may be triggered before the `deviceready` event is fired.
To populate a database using the standard transaction API:
```Javascript
db.transaction(function(tx) {
tx.executeSql('CREATE TABLE IF NOT EXISTS DemoTable (name, score)');
tx.executeSql('INSERT INTO DemoTable VALUES (?,?)', ['Alice', 101]);
tx.executeSql('INSERT INTO DemoTable VALUES (?,?)', ['Betty', 202]);
}, function(error) {
console.log('Transaction ERROR: ' + error.message);
}, function() {
console.log('Populated database OK');
});
```
To check the data using the standard transaction API:
```Javascript
db.transaction(function(tx) {
tx.executeSql('SELECT count(*) AS mycount FROM DemoTable', [], function(tx, rs) {
console.log('Record count (expected to be 2): ' + rs.rows.item(0).mycount);
}, function(tx, error) {
console.log('SELECT error: ' + error.message);
});
});
```
To populate a database using the SQL batch API:
```Javascript
db.sqlBatch([
'CREATE TABLE IF NOT EXISTS DemoTable (name, score)',
[ 'INSERT INTO DemoTable VALUES (?,?)', ['Alice', 101] ],
[ 'INSERT INTO DemoTable VALUES (?,?)', ['Betty', 202] ],
], function() {
console.log('Populated database OK');
}, function(error) {
console.log('SQL batch ERROR: ' + error.message);
});
```
To check the data using the single SQL statement API:
```Javascript
db.executeSql('SELECT count(*) AS mycount FROM DemoTable', [], function(rs) {
console.log('Record count (expected to be 2): ' + rs.rows.item(0).mycount);
}, function(error) {
console.log('SELECT SQL statement ERROR: ' + error.message);
});
```
See the [Sample section](#sample) for a sample with a more detailed explanation.
<!-- END quick tour -->
## Status
- NOT supported by PhoneGap Developer App or PhoneGap Desktop App
- This version uses a `before_plugin_install` hook to install sqlite3 library dependencies from `cordova-sqlite-storage-dependencies` via npm.
- SQLite version `3.15.2` included with the following build settings:
- `SQLITE_THREADSAFE=1`
- `SQLITE_DEFAULT_MEMSTATUS=0`
- `SQLITE_OMIT_DECLTYPE`
- `SQLITE_OMIT_DEPRECATED`
- `SQLITE_OMIT_PROGRESS_CALLBACK`
- `SQLITE_OMIT_SHARED_CACHE`
- `SQLITE_TEMP_STORE=2`
- `SQLITE_OMIT_LOAD_EXTENSION`
- `SQLITE_ENABLE_FTS3`
- `SQLITE_ENABLE_FTS3_PARENTHESIS`
- `SQLITE_ENABLE_FTS4`
- `SQLITE_ENABLE_RTREE`
- `SQLITE_DEFAULT_PAGE_SIZE=1024` and `SQLITE_DEFAULT_CACHE_SIZE=2000` to avoid "potentially distruptive change(s)" from SQLite 3.12.0 ref: <http://sqlite.org/pgszchng2016.html>
- `SQLITE_OS_WINRT` for Windows only
- A recent version of the Cordova CLI (such as `6.5.0`) is recommended. Cordova versions older than `6.0.0` are missing the `cordova-ios@4.0.0` security fixes. In addition it is *required* to use `cordova prepare` in case of cordova-ios older than `4.3.0` (Cordova CLI `6.4.0`).
- Use of other systems such as Cordova Plugman, PhoneGap CLI, PhoneGap Build, and Intel XDK is no longer supported since they do not honor the `before_plugin_install` hook. The supported solution is to use [litehelpers / Cordova-sqlite-evcore-extbuild-free](https://github.com/litehelpers/Cordova-sqlite-evcore-extbuild-free) (available with GPL or commercial license options) or [litehelpers / Cordova-sqlite-legacy-build-support](https://github.com/litehelpers/Cordova-sqlite-legacy-build-support) (limited testing, limited updates)
- The iOS database location is now mandatory, as documented below.
- This version supports the use of two (2) possible Android sqlite database implementations:
- default: lightweight [Android-sqlite-connector](https://github.com/liteglue/Android-sqlite-connector)
- optional: built-in Android database classes (usage described below)
- Support for WP8 along with Windows 8.1/Windows Phone 8.1/Windows 10 using Visual Studio 2015 is available in [litehelpers / Cordova-sqlite-legacy](https://github.com/litehelpers/Cordova-sqlite-legacy).
- The following features are available in [litehelpers / cordova-sqlite-ext](https://github.com/litehelpers/cordova-sqlite-ext):
- REGEXP (Android/iOS/macOS)
- SELECT BLOB data in Base64 format (all platforms Android/iOS/macOS/Windows)
- Pre-populated database (Android/iOS/macOS/Windows)
- Amazon Fire-OS is dropped due to lack of support by Cordova. Android platform version should be used to deploy to Fire-OS 5.0(+) devices. For reference: [cordova/cordova-discuss#32 (comment)](https://github.com/cordova/cordova-discuss/issues/32#issuecomment-167021676)
- Windows platform version (using a customized version of the performant [doo / SQLite3-WinRT](https://github.com/doo/SQLite3-WinRT) C++ component) has the following known limitations:
- Truncation issue with UNICODE `\u0000` character (same as `\0`)
- No background processing
- INCORRECT error code (0) and INCONSISTENT error message (missing actual error info) in error callbacks ref: [litehelpers/Cordova-sqlite-storage#539](https://github.com/litehelpers/Cordova-sqlite-storage/issues/539)
- Not possible to read BLOB column values
- It is **not** possible to use this plugin with the default "Any CPU" target. A specific target CPU type **must** be specified when building an app with this plugin.
- This version has dependency on platform toolset libraries included by Visual Studio 2017 ([litehelpers/Cordova-sqlite-storage#580](https://github.com/litehelpers/Cordova-sqlite-storage/issues/580)). Visual Studio 2015 is now supported by [litehelpers / Cordova-sqlite-legacy-build-support](https://github.com/litehelpers/Cordova-sqlite-legacy-build-support).
- Windows platform version uses `UTF-16le` internal database encoding while the other platform versions use `UTF-8` internal encoding. (`UTF-8` internal encoding is preferred ref: [litehelpers/Cordova-sqlite-storage#652](https://github.com/litehelpers/Cordova-sqlite-storage/issues/652))
- Certain close/delete scenarios in the test suite not working on Windows
- The macOS platform version ("osx" platform) has not been tested in a release build and should be considered pre-alpha.
- FTS3, FTS4, and R-Tree support is tested working OK in this version (for all target platforms in this version branch Android/iOS/macOS/Windows)
- Android is supported back to SDK 10 (a.k.a. Gingerbread, Android 2.3.3); support for older versions is available upon request.
- iOS versions supported: 8.x/9.x/10.x (see [deviations section](#deviations) below for differences in case of WKWebView)
- In case of memory issues please use smaller transactions or use the version (with GPL or commercial license options) at: [litehelpers / Cordova-sqlite-evcore-extbuild-free](https://github.com/litehelpers/Cordova-sqlite-evcore-extbuild-free)
<!-- END Status -->
## Announcements
- Resolved transaction problem after window.location (page) change with possible data loss ref: [litehelpers/Cordova-sqlite-storage#666](https://github.com/litehelpers/Cordova-sqlite-storage/issues/666)
- This version references Windows platform toolset v141 to support Visual Studio 2017. Visual Studio 2015 is now supported by [litehelpers / Cordova-sqlite-legacy-build-support](https://github.com/litehelpers/Cordova-sqlite-legacy-build-support).
- [brodybits / cordova-sqlite-storage-starter-app](https://github.com/brodybits/cordova-sqlite-storage-starter-app) project is a CC0 (public domain) starting point and may also be used to reproduce issues with this plugin. In addition [brodybits / cordova-sqlite-test-app](https://github.com/brodybits/cordova-sqlite-test-app) may be used to reproduce issues with other versions of this plugin.
- The Lawnchair adapter is now moved to [litehelpers / cordova-sqlite-lawnchair-adapter](https://github.com/litehelpers/cordova-sqlite-lawnchair-adapter).
- [litehelpers / cordova-sqlite-ext](https://github.com/litehelpers/cordova-sqlite-ext) now supports SELECT BLOB data in Base64 format on all platforms in addition to REGEXP (Android/iOS/macOS) and pre-populated database (all platforms).
- [brodybits / sql-promise-helper](https://github.com/brodybits/sql-promise-helper) provides a Promise-based API wrapper.
- [nolanlawson / pouchdb-adapter-cordova-sqlite](https://github.com/nolanlawson/pouchdb-adapter-cordova-sqlite) supports this plugin along with other implementations such as [nolanlawson / sqlite-plugin-2](https://github.com/nolanlawson/sqlite-plugin-2) and [Microsoft / cordova-plugin-websql](https://github.com/Microsoft/cordova-plugin-websql).
- macOS ("osx" platform) is now supported
- New [litehelpers / Cordova-sqlite-evcore-extbuild-free](https://github.com/litehelpers/Cordova-sqlite-evcore-extbuild-free) version with Android JSON and SQL statement handling implemented in C, as well as support for PhoneGap Build, Intel XDK, etc., available with GPL or commercial license options. Handles large SQL batches in less than half the time as this version. Also supports arbitrary database location on Android.
- Published [brodybits / Cordova-quick-start-checklist](https://github.com/brodybits/Cordova-quick-start-checklist) and [brodybits / Avoiding-some-Cordova-pitfalls](https://github.com/brodybits/Avoiding-some-Cordova-pitfalls).
- Android platform version uses the lightweight [Android-sqlite-connector](https://github.com/liteglue/Android-sqlite-connector) by default configuration (may be changed as described below).
- Self-test functions to verify proper installation and operation of this plugin.
- More explicit `openDatabase` and `deleteDatabase` `iosDatabaseLocation` option
- Added simple sql batch function
- [MetaMemoryT / websql-promise](https://github.com/MetaMemoryT/websql-promise) now provides a Promises-based interface to both Web SQL and this plugin
<!-- END Announcements -->
## Highlights
- Drop-in replacement for HTML5/[Web SQL API](http://www.w3.org/TR/webdatabase/): the only change should be to replace the static `window.openDatabase()` factory call with `window.sqlitePlugin.openDatabase()`, with parameters as documented below. Known deviations are documented in the [deviations section](#deviations) below.
- Failure-safe nested transactions with batch processing optimizations (according to HTML5/[Web SQL API](http://www.w3.org/TR/webdatabase/))
- API (based on HTML5/[Web SQL API](http://www.w3.org/TR/webdatabase/)) is designed to be as flexible as possible but does not allow any transactions to _remain_ hanging open.
- As described in [this posting](http://brodyspark.blogspot.com/2012/12/cordovaphonegap-sqlite-plugins-offer.html):
- Keeps sqlite database in known, platform specific user data location on all platforms (Android/iOS/macOS/Windows), which can be reconfigured on iOS/macOS. Whether or not the database on the iOS platform is synchronized to iCloud depends on the selected database location.
- No arbitrary size limit. SQLite limits described at: <http://www.sqlite.org/limits.html>
- Also tested for multi-page applications with window location changes
- This project is self-contained though with sqlite3 dependencies auto-fetched by npm. There are no dependencies on other plugins such as cordova-plugin-file.
- Windows platform version uses a customized version of the performant [doo / SQLite3-WinRT](https://github.com/doo/SQLite3-WinRT) C++ component.
- [SQLCipher](https://www.zetetic.net/sqlcipher/) support for Android/iOS/macOS/Windows is available in: [litehelpers / Cordova-sqlcipher-adapter](https://github.com/litehelpers/Cordova-sqlcipher-adapter)
- Intellectual property:
- All source code is tracked to the original author in git
- Major authors are tracked in AUTHORS.md
- License of each component is tracked in LICENSE.md
- History of this project is also described in HISTORY.md
**TIP:** It is possible to migrate from Cordova to a pure native solution and continue using the data stored by this plugin.
<!-- END Highlights -->
## Getting started
### Recommended prerequisites
- Install a recent version of Cordova CLI, create a simple app with no plugins, and run it on the desired target platforms.
- Add a very simple plugin such as `cordova-plugin-dialogs` or an echo plugin and get it working. Ideally you should be able to handle a callback with some data coming from a prompt.
These prereqisites are very well documented in a number of excellent resources including:
- <http://cordova.apache.org/> (redirected from <http://cordova.io>)
- <http://www.tutorialspoint.com/cordova/>
- <https://ccoenraets.github.io/cordova-tutorial/>
- <https://www.toptal.com/mobile/developing-mobile-applications-with-apache-cordova>
- <http://www.tutorialspoint.com/cordova/index.htm>
More resources can be found by <https://www.google.com/search?q=cordova+tutorial>. There are even some tutorials available on YouTube as well.
In addition, this guide assumes a basic knowledge of some key JavaScript concepts such as variables, function calls, and callback functions. There is an excellent explanation of JavaScript callbacks at <http://cwbuecheler.com/web/tutorials/2013/javascript-callbacks/>.
**MAJOR TIPS:** As described in the [Installing](#installing) section:
- It is recommended to use the `--save` flag when installing plugins to track them in `config.xml`. If all plugins are tracked in `config.xml` then there is no need to commit the `plugins` subdirectory tree into the source repository.
- In general it is *not* recommended to commit the `platforms` subdirectory tree into the source repository.
**NOTICE:** This plugin is only supported with the Cordova CLI. This plugin is *not* supported with other Cordova/PhoneGap systems such as PhoneGap CLI, PhoneGap Build, Plugman, Intel XDK, Webstorm, etc.
### Windows platform notes
The Windows platform can present a number of challenges which increase when using this plugin. The following tips are recommended for getting started with Windows:
- First start to build and run an app on another platform such as Android or iOS with this plugin.
- Try working with a very simple app using simpler plugins such as cordova-plugin-dialogs and possibly cordova-plugin-file on the Windows platform.
- Read through the **Windows platform usage** of the [Installing](#installing) section.
- Then try adding this plugin to a very simple app such as [brodybits / cordova-sqlite-test-app](https://github.com/brodybits/cordova-sqlite-test-app) and running the Windows project in the Visual Studio GUI with a specific target CPU selected. **WARNING:** It is not possible to use this plugin with the "Any CPU" target.
### Quick installation
Use the following command to install this plugin from the Cordova CLI:
```shell
cordova plugin add cordova-sqlite-storage --save
```
Add any desired platform(s) if not already present, for example:
```shell
cordova platform add android
```
**OPTIONAL:** prepare before building (**MANDATORY** for cordova-ios older than `4.3.0` (Cordova CLI `6.4.0`))
```shell
cordova prepare
```
or to prepare for a single platform, Android for example:
```shell
cordova prepare android
```
Please see the [Installing](#installing) section for more details.
**NOTE:** The new [brodybits / cordova-sqlite-test-app](https://github.com/brodybits/cordova-sqlite-test-app) project includes the echo test, self test, and string test described below along with some more sample functions.
<!-- END Quick installation -->
### Self test
Try the following programs to verify successful installation and operation:
**Echo test** - verify successful installation and build:
```js
document.addEventListener('deviceready', function() {
window.sqlitePlugin.echoTest(function() {
console.log('ECHO test OK');
});
});
```
**Self test** - automatically verify basic database access operations including opening a database; basic CRUD operations (create data in a table, read the data from the table, update the data, and delete the data); close and delete the database:
```js
document.addEventListener('deviceready', function() {
window.sqlitePlugin.selfTest(function() {
console.log('SELF test OK');
});
});
```
**NOTE:** It may be easier to use a JavaScript or native `alert` function call along with (or instead of) `console.log` to verify that the installation passes both tests. Same for the SQL string test variations below. (Note that the Windows platform does not support the standard `alert` function, please use `cordova-plugin-dialogs` instead.)
### SQL string test
This test verifies that you can open a database, execute a basic SQL statement, and get the results (should be `TEST STRING`):
```js
document.addEventListener('deviceready', function() {
var db = window.sqlitePlugin.openDatabase({name: 'test.db', location: 'default'});
db.transaction(function(tr) {
tr.executeSql("SELECT upper('Test string') AS upperString", [], function(tr, rs) {
console.log('Got upperString result: ' + rs.rows.item(0).upperString);
});
});
});
```
Here is a variation that uses a SQL parameter instead of a string literal:
```js
document.addEventListener('deviceready', function() {
var db = window.sqlitePlugin.openDatabase({name: 'test.db', location: 'default'});
db.transaction(function(tr) {
tr.executeSql('SELECT upper(?) AS upperString', ['Test string'], function(tr, rs) {
console.log('Got upperString result: ' + rs.rows.item(0).upperString);
});
});
});
```
### Moving forward
It is recommended to read through the [usage](#usage) and [sample](#sample) sections before building more complex applications. In general it is recommended to start by doing things one step at a time, especially when an application does not work as expected.
The new [brodybits / cordova-sqlite-test-app](https://github.com/brodybits/cordova-sqlite-test-app) sample is intended to be a boilerplate to reproduce and demonstrate any issues you may have with this plugin. You may also use it as a starting point to build a new app.
In case you get stuck with something please read through the [support](#support) section and follow the instructions before raising an issue. Professional support is also available by contacting: <sales@litehelpers.net>
### Plugin usage examples
- [brodybits / cordova-sqlite-storage-starter-app](https://github.com/brodybits/cordova-sqlite-storage-starter-app)
- <http://stackoverflow.com/questions/26604952/a-simple-cordova-android-example-including-sqlite-read-write-and-search>
### Plugin tutorials
- <https://phonegappro.com/tutorials/phonegap-sqlite-tutorial-with-example-apache-cordova/>
**NOTICE:** The above tutorial shows `cordova plugin add cordova-sqlite-storage` with the `--save` flag missing. Please be sure to use the `--save` flag to keep the plugins in `config.xml`.
Other plugin tutorials wanted ref: [litehelpers/Cordova-sqlite-storage#609](https://github.com/litehelpers/Cordova-sqlite-storage/issues/609)
### SQLite resources
- <http://www.tutorialspoint.com/sqlite/index.htm> with a number of helpful articles
### Some other Cordova resources
- <http://www.tutorialspoint.com/cordova/cordova_file_system.htm>
<!-- END Getting started -->
## Some apps using this plugin
- [Trailforks Mountain Bike Trail Map App](http://www.trailforks.com/apps/map/) with a couple of nice videos at: <http://www.pinkbike.com/news/trailforks-app-released.html>
- [Get It Done app](http://getitdoneapp.com/) by [marcucio.com](http://marcucio.com/)
- [KAAHE Health Encyclopedia](http://www.kaahe.org/en/index.php?option=com_content&view=article&id=817): Official health app of the Kingdom of Saudi Arabia.
- [Larkwire](http://www.larkwire.com/) (iOS platform): Learn bird songs the fun way
- [Tangorin](https://play.google.com/store/apps/details?id=com.tangorin.app) (Android) Japanese Dictionary at [tangorin.com](http://tangorin.com/)
- [GeoWiz.Biz](http://www.geowiz.biz/) Truck Tracker app with a [Personal Edition](http://geowiz.biz/personal-edition-login) available in the Android and iOS app stores
<!-- END Some apps using this plugin -->
## Security
### Security of sensitive data
According to [Web SQL Database API 7.2 Sensitivity of data](https://www.w3.org/TR/webdatabase/#sensitivity-of-data):
>User agents should treat persistently stored data as potentially sensitive; it's quite possible for e-mails, calendar appointments, health records, or other confidential documents to be stored in this mechanism.
>
>To this end, user agents should ensure that when deleting data, it is promptly deleted from the underlying storage.
Unfortunately this plugin will not actually overwrite the deleted content unless the [secure_delete PRAGMA](https://www.sqlite.org/pragma.html#pragma_secure_delete) is used.
### SQL injection
As "strongly recommended" by [Web SQL Database API 8.5 SQL injection](https://www.w3.org/TR/webdatabase/#sql-injection):
>Authors are strongly recommended to make use of the `?` placeholder feature of the `executeSql()` method, and to never construct SQL statements on the fly.
<!-- END Security -->
# Avoiding data loss
- Double-check that the application code follows the documented API for SQL statements, parameter values, success callbacks, and error callbacks.
- For standard Web SQL transactions include a transaction error callback with the proper logic that indicates to the user if data cannot be stored for any reason. In case of individual SQL error handlers be sure to indicate to the user if there is any issue with storing data.
- For single statement and batch transactions include an error callback with logic that indicates to the user if data cannot be stored for any reason.
<!-- Avoiding data loss -->
## Deviations
### Some known deviations from the Web SQL database standard
- The `window.sqlitePlugin.openDatabase` static factory call takes a different set of parameters than the standard Web SQL `window.openDatabase` static factory call. In case you have to use existing Web SQL code with no modifications please see the **Web SQL replacement tip** below.
- This plugin does *not* support the database creation callback or standard database versions. Please read the **Database schema versions** section below for tips on how to support database schema versioning.
- This plugin does *not* support the synchronous Web SQL interfaces.
- Known issues with handling of certain ASCII/UNICODE characters as described below.
- It is possible to request a SQL statement list such as "SELECT 1; SELECT 2" within a single SQL statement string, however the plugin will only execute the first statement and silently ignore the others ref: [litehelpers/Cordova-sqlite-storage#551](https://github.com/litehelpers/Cordova-sqlite-storage/issues/551)
- It is possible to insert multiple rows like: `transaction.executeSql('INSERT INTO MyTable VALUES (?,?),(?,?)', ['Alice', 101, 'Betty', 102]);` which was not supported by SQLite 3.6.19 as referenced by [Web SQL API section 5](https://www.w3.org/TR/webdatabase/#web-sql). The iOS WebKit Web SQL implementation seems to support this as well.
- Unlike the HTML5/[Web SQL API](http://www.w3.org/TR/webdatabase/) this plugin handles executeSql calls with too few parameters without error reporting. In case of too many parameters this plugin reports error code 0 (SQLError.UNKNOWN_ERR) while Android/iOS (WebKit) Web SQL correctly reports error code 5 (SQLError.SYNTAX_ERR) ref: https://www.w3.org/TR/webdatabase/#dom-sqlexception-code-syntax
- Positive and negative `Infinity` SQL parameter argument values are treated like `null` by this plugin on Android and iOS ref: [litehelpers/Cordova-sqlite-storage#405](https://github.com/litehelpers/Cordova-sqlite-storage/issues/405)
- Positive and negative `Infinity` result values cause a crash on iOS/macOS cases ref: [litehelpers/Cordova-sqlite-storage#405](https://github.com/litehelpers/Cordova-sqlite-storage/issues/405)
- Known issue(s) with of certain ASCII/UNICODE characters as described below.
- Boolean `true` and `false` values are handled by converting them to the "true" and "false" TEXT string values, same as WebKit Web SQL on Android and iOS. This does not seem to be 100% correct as discussed in: [litehelpers/Cordova-sqlite-storage#545](https://github.com/litehelpers/Cordova-sqlite-storage/issues/545)
- A number of uncategorized errors such as CREATE VIRTUAL TABLE USING bogus module are reported with error code 5 (SQLError.SYNTAX_ERR) on Android/iOS/macOS by both (WebKit) Web SQL and this plugin.
- Issues with error code on Windows as well as Android with the `androidDatabaseImplementation: 2` setting described below.
- In case of an issue that causes an API function to throw an exception (Android/iOS WebKit) Web SQL includes includes a code member with value of 0 (SQLError.UNKNOWN_ERR) in the exception while the plugin includes no such code member.
- This plugin supports some non-standard features as documented below.
- Results of SELECT with BLOB data such as `SELECT LOWER(X'40414243') AS myresult`, `SELECT X'40414243' AS myresult`, or reading data stored by `INSERT INTO MyTable VALUES (X'40414243')` are not consistent on Android in case the built-in Android database is used (using the `androidDatabaseImplementation: 2` setting in `window.sqlitePlugin.openDatabase`) or Windows. (These work with Android/iOS WebKit Web SQL and have been supported by SQLite for a number of years.)
- Whole number parameter argument values such as `42`, `-101`, or `1234567890123` are handled as INTEGER values by this plugin on Android, iOS (default UIWebView), and Windows while they are handled as REAL values by (WebKit) Web SQL and this plugin on macOS or iOS with WKWebView. This is evident in certain test operations such as `SELECT ? as myresult` or `SELECT TYPEOF(?) as myresult` and storage in a field with TEXT affinity.
- INTEGER, REAL, +/- `Infinity`, `NaN`, `null`, `undefined` parameter argument values are handled as TEXT string values on Android in case the built-in Android database (`androidDatabaseImplementation: 2` setting) is used. (This is evident in certain test operations such as `SELECT ? as myresult` or `SELECT TYPEOF(?) as myresult` and storage in a field with TEXT affinity.)
- In case of invalid transaction callback arguments such as string values the plugin attempts to execute the transaction while (WebKit) Web SQL would throw an exception.
- The plugin handles invalid SQL arguments array values such as `false`, `true`, or a string as if there were no arguments while (WebKit) Web SQL would throw an exception. NOTE: In case of a function in place of the SQL arguments array WebKit Web SQL would report a transaction error while the plugin would simply ignore the function.
- In case of invalid SQL callback arguments such as string values the plugin may execute the SQL and signal transaction success or failure while (WebKit) Web SQL would throw an exception.
- In certain cases such as `transaction.executeSql(null)` or `transaction.executeSql(undefined)` the plugin throws an exception while (WebKit) Web SQL indicates a transaction failure.
- In certain cases such as `transaction.executeSql()` with no arguments (Android/iOS WebKit) Web SQL includes includes a code member with value of 0 (SQLError.UNKNOWN_ERR) in the exception while the plugin includes no such code member.
- If the SQL arguments are passed in an `Array` subclass object where the `constructor` does not point to `Array` then the SQL arguments are ignored by the plugin.
- The results data objects are not immutable as specified/implied by [Web SQL API section 4.5](https://www.w3.org/TR/webdatabase/#database-query-results).
### Security of deleted data
See **Security of sensitive data** in the [Security](#security) section above.
### Other differences with WebKit Web SQL implementations
- In case of ignored INSERT OR IGNORE statement WebKit Web SQL (Android/iOS) reports insertId with an old INSERT row id value while the plugin reports insertId: undefined.
- In case of a SQL error handler that does not recover the transaction, WebKit Web SQL (Android/iOS) would incorrectly report error code 0 while the plugin would report the same error code as in the SQL error handler. (In case of an error with no SQL error handler then Android/iOS WebKit Web SQL would report the same error code that would have been reported in the SQL error hander.)
- In case a transaction function throws an exception, the message and code if present are reported by the plugin but *not* by (WebKit) Web SQL.
- SQL error messages are inconsistent on Windows.
- There are some other differences in the SQL error messages reported by WebKit Web SQL and this plugin.
<!-- END Deviations -->
## Known issues
- The iOS/macOS platform version does not support certain rapidly repeated open-and-close or open-and-delete test scenarios due to how the implementation handles background processing.
- As described below, auto-vacuum is NOT enabled by default.
- The Android platform version does not always handle four-byte UTF-8 characters emoji characters such as `\u1F603` (SMILING FACE, MOUTH OPEN) correctly ref: [litehelpers/Cordova-sqlite-storage#564](https://github.com/litehelpers/Cordova-sqlite-storage/issues/564). It is sometimes possible to store and retrieve such characters but certain operations such as hex conversions do not work properly with the default [Android-sqlite-connector](https://github.com/liteglue/Android-sqlite-connector) database implementation. It is suspected that such characters would be stored incorrectly by the default Android platform version. This is not an issue in case the built-in Android database is used (using the `androidDatabaseImplementation: 2` setting in `window.sqlitePlugin.openDatabase`)
- It is possible to request a SQL statement list such as "SELECT 1; SELECT 2" within a single SQL statement string, however the plugin will only execute the first statement and silently ignore the others ref: [litehelpers/Cordova-sqlite-storage#551](https://github.com/litehelpers/Cordova-sqlite-storage/issues/551)
- INSERT statement that affects multiple rows (due to SELECT cause or using TRIGGER(s), for example) reports incorrect rowsAffected on Android in case the built-in Android database used (using the `androidDatabaseImplementation` option in `window.sqlitePlugin.openDatabase`)
- Memory issue observed when adding a large number of records due to the JSON implementation which is improved in [litehelpers / Cordova-sqlite-evcore-extbuild-free](https://github.com/litehelpers/Cordova-sqlite-evcore-extbuild-free) (available with GPL or commercial license options)
- Infinity (positive or negative) values are not supported on Android/iOS/macOS due to issues described above including a possible crash on iOS/macOS ref: [litehelpers/Cordova-sqlite-storage#405](https://github.com/litehelpers/Cordova-sqlite-storage/issues/405)
- A stability issue was reported on the iOS platform version when in use together with [SockJS](http://sockjs.org/) client such as [pusher-js](https://github.com/pusher/pusher-js) at the same time (see [litehelpers/Cordova-sqlite-storage#196](https://github.com/litehelpers/Cordova-sqlite-storage/issues/196)). The workaround is to call sqlite functions and [SockJS](http://sockjs.org/) client functions in separate ticks (using setTimeout with 0 timeout).
- SQL errors are reported with an INCORRECT error code (0) on Windows ref: [litehelpers/Cordova-sqlite-storage#539](https://github.com/litehelpers/Cordova-sqlite-storage/issues/539). In certain cases SQL errors are also reported with error code 0 on Android in case the built-in Android database is used (using the `androidDatabaseImplementation: 2` setting in `window.sqlitePlugin.openDatabase`).
- Possible crash on Android when using Unicode emoji and other 4-octet UTF-8 characters due to [Android bug 81341](https://code.google.com/p/android/issues/detail?id=81341), which *should* be fixed in Android 6.x
- Close/delete database bugs described below.
- When a database is opened and deleted without closing, the iOS/macOS platform version is known to leak resources.
- It is NOT possible to open multiple databases with the same name but in different locations (iOS/macOS platform version).
Some more known issues are tracked in the [open cordova-sqlite-storage bug-general issues](https://github.com/litehelpers/Cordova-sqlite-storage/issues?q=is%3Aissue+is%3Aopen+label%3Abug-general).
<!-- END Known issues -->
## Other limitations
- ~~The db version, display name, and size parameter values are not supported and will be ignored.~~ (No longer supported by the API)
- Absolute and relative subdirectory path(s) are not tested or supported.
- This plugin will not work before the callback for the 'deviceready' event has been fired, as described in **Usage**. (This is consistent with the other Cordova plugins.)
- Extremely large records are not supported by this plugin version. It is recommended to store images and similar binary data in separate files. TBD: specify maximum record. For future consideration: support in a version such as [litehelpers / Cordova-sqlite-evcore-extbuild-free](https://github.com/litehelpers/Cordova-sqlite-evcore-extbuild-free) (available with GPL or commercial license options)
- This plugin version will not work within a web worker (not properly supported by the Cordova framework). Use within a web worker is supported for Android and iOS in: [litehelpers / Cordova-sqlite-evplus-legacy-workers-free](https://github.com/litehelpers/Cordova-sqlite-evplus-legacy-workers-free) (available with GPL or premium commercial license options)
- In-memory database `db=window.sqlitePlugin.openDatabase({name: ':memory:', ...})` is currently not supported.
- The Android platform version cannot properly support more than 100 open database files due to the threading model used.
- SQL error messages on Windows platform version are not consistent with Android/iOS/macOS platform versions.
- UNICODE `\u2028` (line separator) and `\u2029` (paragraph separator) characters are currently not supported and known to be broken in iOS, macOS, and Android platform versions due to JSON issues reported in [Cordova bug CB-9435](https://issues.apache.org/jira/browse/CB-9435) and [cordova/cordova-discuss#57](https://github.com/cordova/cordova-discuss/issues/57). This is fixed with a workaround for iOS/macOS in: [litehelpers / Cordova-sqlite-evplus-legacy-free](https://github.com/litehelpers/Cordova-sqlite-evplus-legacy-free) and [litehelpers / Cordova-sqlite-evplus-legacy-attach-detach-free](https://github.com/litehelpers/Cordova-sqlite-evplus-legacy-attach-detach-free) (available with GPL or special commercial license options) as well as [litehelpers / Cordova-sqlite-evplus-legacy-workers-free](https://github.com/litehelpers/Cordova-sqlite-evplus-legacy-workers-free) (available with GPL or premium commercial license options)
- The BLOB data type is not fully supported by this version branch. SELECT BLOB in Base64 format is supported by [litehelpers / cordova-sqlite-ext](https://github.com/litehelpers/cordova-sqlite-ext) (permissive license terms) and [litehelpers / Cordova-sqlite-evcore-extbuild-free](https://github.com/litehelpers/Cordova-sqlite-evcore-extbuild-free) (GPL or commercial license options).
- Truncation in case of UNICODE `\u0000` (same as `\0`) character on Android (default Android-sqlite-connector database implementation) and Windows
- Case-insensitive matching and other string manipulations on Unicode characters, which is provided by optional ICU integration in the sqlite source and working with recent versions of Android, is not supported for any target platforms.
- The iOS/macOS platform version uses a thread pool but with only one thread working at a time due to "synchronized" database access.
- Some large query results may be slow, also due to the JSON implementation.
- ATTACH to another database file is not supported by this version. Attach/detach is supported (along with the memory and iOS UNICODE `\u2028` line separator / `\u2029` paragraph separator fixes) in: [litehelpers / Cordova-sqlite-evplus-legacy-attach-detach-free](https://github.com/litehelpers/Cordova-sqlite-evplus-legacy-attach-detach-free) (available with GPL or special commercial license options)
- UPDATE/DELETE with LIMIT or ORDER BY is not supported.
- WITH clause is not supported by older Android versions in case the `androidDatabaseImplementation: 2` (built-in android.database implementation) option is used.
- User-defined savepoints are not supported and not expected to be compatible with the transaction locking mechanism used by this plugin. In addition, the use of BEGIN/COMMIT/ROLLBACK statements is not supported.
- Problems have been reported when using this plugin with Crosswalk (for Android). It may help to install Crosswalk as a plugin instead of using Crosswalk to create the project.
- Does not work with [axemclion / react-native-cordova-plugin](https://github.com/axemclion/react-native-cordova-plugin) since the `window.sqlitePlugin` object is *not* properly exported (ES5 feature). It is recommended to use [andpor / react-native-sqlite-storage](https://github.com/andpor/react-native-sqlite-storage) for SQLite database access with React Native Android/iOS instead.
Some more limitations are tracked in the [open cordova-sqlite-storage doc-todo issues](https://github.com/litehelpers/Cordova-sqlite-storage/issues?q=is%3Aissue+is%3Aopen+label%3Adoc-todo).
<!-- END Other limitations -->
## Further testing needed
- Integration with PhoneGap developer app
- Use within [InAppBrowser](http://docs.phonegap.com/en/edge/cordova_inappbrowser_inappbrowser.md.html)
- Use within an iframe (see [litehelpers/Cordova-sqlite-storage#368 (comment)](https://github.com/litehelpers/Cordova-sqlite-storage/issues/368#issuecomment-154046367))
- Date/time handling
- Maximum record size supported
- Actual behavior when using SAVEPOINT(s)
- R-Tree is not fully tested with Android
- Some more UNICODE characters
- ORDER BY random() (ref: [litehelpers/Cordova-sqlite-storage#334](https://github.com/litehelpers/Cordova-sqlite-storage/issues/334))
- UPDATE/DELETE with LIMIT or ORDER BY (newer Android/iOS versions)
- Integration with JXCore for Cordova (must be built without sqlite(3) built-in)
- Delete an open database inside a statement or transaction callback.
- WITH clause (not supported by some older sqlite3 versions)
- Handling of invalid transaction and transaction.executeSql arguments
- Use of database locations on macOS
- Extremely large and small INTEGER and REAL values ref: [litehelpers/Cordova-sqlite-storage#627](https://github.com/litehelpers/Cordova-sqlite-storage/issues/627))
- More emojis and other 4-octet UTF-8 characters
- `?NNN`/`:AAA`/`@AAAA`/`$AAAA` parameter placeholders ref: <https://www.sqlite.org/lang_expr.html#varparam>, <https://www.sqlite.org/c3ref/bind_blob.html>)
- Single-statement and SQL batch transaction calls with invalid arguments (TBD behavior subject to change)
- Other [open Cordova-sqlite-storage testing issues](https://github.com/litehelpers/Cordova-sqlite-storage/issues?q=is%3Aissue+is%3Aopen+label%3Atesting)
<!-- END Further testing needed -->
## Some tips and tricks
- If you run into problems and your code follows the asynchronous HTML5/[Web SQL](http://www.w3.org/TR/webdatabase/) transaction API, you can try opening a test database using `window.openDatabase` and see if you get the same problems.
- In case your database schema may change, it is recommended to keep a table with one row and one column to keep track of your own schema version number. It is possible to add it later. The recommended schema update procedure is described below.
<!-- END Some tips and tricks -->
## Pitfalls
### Some common pitfall(s)
- If a database is opened using the standard `window.openDatabase` call it will not have any of the benefits of this plugin and features such as the `sqlBatch` call would not be available.
- It is NOT allowed to execute sql statements on a transaction that has already finished, as described below. This is consistent with the HTML5/[Web SQL API](http://www.w3.org/TR/webdatabase/).
- The plugin class name starts with "SQL" in capital letters, but in Javascript the `sqlitePlugin` object name starts with "sql" in small letters.
- Attempting to open a database before receiving the 'deviceready' event callback.
- Inserting STRING into ID field
- Auto-vacuum is NOT enabled by default. It is recommended to periodically VACUUM the database.
- Transactions on a database are run sequentially. A large transaction could block smaller transactions requested afterwards.
### Some weird pitfall(s)
- intent whitelist: blocked intent such as external URL intent *may* cause this and perhaps certain Cordova plugin(s) to misbehave (see [litehelpers/Cordova-sqlite-storage#396](https://github.com/litehelpers/Cordova-sqlite-storage/issues/396))
### Angular/ngCordova/Ionic-related pitfalls
- Angular/ngCordova/Ionic controller/factory/service callbacks may be triggered before the 'deviceready' event is fired
- As discussed in [litehelpers/Cordova-sqlite-storage#355](https://github.com/litehelpers/Cordova-sqlite-storage/issues/355), it may be necessary to install ionic-plugin-keyboard
- Navigation items such as root page can be tricky on Ionic 2 ref: [litehelpers/Cordova-sqlite-storage#613](https://github.com/litehelpers/Cordova-sqlite-storage/issues/613)
### Windows platform pitfalls
- This plugin does **not** work with the default "Any CPU" target. A specific, valid CPU target platform **must** be specified.
- It is **not** allowed to change the app ID in the Windows platform project. As described in the **Windows platform usage** of the [Installing](#installing) section a Windows-specific app ID may be declared using the `windows-identity-name` attribute or "WindowsStoreIdentityName" setting.
- A problem locating `SQLite3.md` generally means that there was a problem building the C++ library.
- Visual Studio 2015 is no longer supported by this version. Visual Studio 2015 is now supported by [litehelpers / Cordova-sqlite-legacy-build-support](https://github.com/litehelpers/Cordova-sqlite-legacy-build-support).
### General Cordova pitfalls
Documented in: [brodybits / Avoiding-some-Cordova-pitfalls](https://github.com/brodybits/Avoiding-some-Cordova-pitfalls)
### General SQLite pitfalls
From <https://www.sqlite.org/datatype3.html#section_1>:
> SQLite uses a more general dynamic type system.
This is generally nice to have, especially in conjunction with a dynamically typed language such as JavaScript. Here are some major SQLite data typing principles:
- From <https://www.sqlite.org/datatype3.html#section_3>: the CREATE TABLE SQL statement declares each column with one of the following type affinities: TEXT, NUMERIC, INTEGER, REAL, or BLOB.
- From <https://www.sqlite.org/datatype3.html#section_3_1> with column type affinity determination rules: it should be possible to do CREATE TABLE with columns of almost any type name (for example: `CREATE TABLE MyTable (data ABC);`) and each column type affinity is determined according to pattern matching. If a declared column type name does not match any of the patterns the column has NUMERIC affinity.
- From <https://www.sqlite.org/datatype3.html#section_3_2>: a column with no data type name specified actually gets the BLOB affinity.
However there are some possible gotchas:
1. From <https://www.sqlite.org/datatype3.html#section_3_2>:
> Note that a declared type of "FLOATING POINT" would give INTEGER affinity, not REAL affinity, due to the "INT" at the end of "POINT". And the declared type of "STRING" has an affinity of NUMERIC, not TEXT.
2. From ibid: a column declared as "DATETIME" has NUMERIC affinity, which gives no hint whether an INTEGER Unix time value, a REAL Julian time value, or possibly even a TEXT ISO8601 date/time string may be stored (further refs: <https://www.sqlite.org/datatype3.html#section_2_2>, <https://www.sqlite.org/datatype3.html#section_3>)
From <https://groups.google.com/forum/#!topic/phonegap/za7z51_fKRw>, as discussed in [litehelpers/Cordova-sqlite-storage#546](https://github.com/litehelpers/Cordova-sqlite-storage/issues/546): it was discovered that are some more points of possible confusion with date/time. For example, there is also a `datetime` function that returns date/time in TEXT string format. This should be considered a case of "DATETIME" overloading since SQLite is *not* case sensitive. This could really become confusing if different programmers or functions consider date/time to be stored in different ways.
FUTURE TBD: Proper date/time handling will be further tested and documented at some point.
<!-- END pitfalls -->
## Major TODOs
- More formal documentation of API, especially for non-standard functions
- IndexedDBShim adapter
- Further cleanup of [support](#support) section
- Resolve or document remaining [open cordova-sqlite-storage bugs](https://github.com/litehelpers/Cordova-sqlite-storage/issues?q=is%3Aissue+is%3Aopen+label%3Abug-general)
- Resolve [cordova-sqlite-help doc-todo issues](https://github.com/litehelpers/Cordova-sqlite-help/issues?q=is%3Aissue%20label%3Adoc-todo) and [cordova-sqlite-storage doc-todo issues](https://github.com/litehelpers/Cordova-sqlite-storage/issues?q=is%3Aissue+is%3Aopen+label%3Adoc-todo)
## For future considertion
- Auto-vacuum option
- Browser platform
- Support for extremely large records in a version such as [litehelpers / Cordova-sqlite-evcore-extbuild-free](https://github.com/litehelpers/Cordova-sqlite-evcore-extbuild-free) (available with GPL or commercial license options)
- Integrate with some other libraries such as Sequelize, Squel.js, WebSqlSync, Persistence.js, Knex, etc.
## Alternatives
### Other versions
- [litehelpers / cordova-sqlite-ext](https://github.com/litehelpers/cordova-sqlite-ext) - version with REGEXP (Android/iOS/macOS), SELECT BLOB in Base64 format (all platforms Android/iOS/macOS/Windows), and pre-populated databases (all platforms Android/iOS/macOS/Windows)
- [litehelpers / Cordova-sqlite-legacy-build-support](https://github.com/litehelpers/Cordova-sqlite-legacy-build-support) - maintenance of WP8 version along with Windows 8.1/Windows Phone 8.1 and the other supported platforms Android/iOS/macOS/Windows 10; limited support for PhoneGap CLI/PhoneGap Build/plugman/Intel XDK; limited testing; limited updates
- [litehelpers / Cordova-sqlcipher-adapter](https://github.com/litehelpers/Cordova-sqlcipher-adapter) - supports [SQLCipher](https://www.zetetic.net/sqlcipher/) for Android/iOS/macOS/Windows
- [litehelpers / Cordova-sqlite-evcore-extbuild-free](https://github.com/litehelpers/Cordova-sqlite-evcore-extbuild-free) - Enhancements for Android: JSON and SQL statement handling implemented in C, supports larger transactions and handles large SQL batches in less than half the time as this version. Supports arbitrary database location on Android. Support for build environments such as PhoneGap Build and Intel XDK. Available with GPL or commercial license options. Also includes REGEXP (Android/iOS/macOS) and SELECT BLOB in Base64 format (all platforms Android/iOS/macOS/Windows).
- [litehelpers / Cordova-sqlite-evplus-legacy-workers-free](https://github.com/litehelpers/Cordova-sqlite-evplus-legacy-workers-free) - version with support for web workers, includes internal memory improvements to support larger transactions (Android/iOS) and fix to support all Unicode characters (iOS) (with GPL or premium commercial license options)
- [litehelpers / Cordova-sqlite-evplus-legacy-free](https://github.com/litehelpers/Cordova-sqlite-evplus-legacy-free) - internal memory improvements to support larger transactions (Android/iOS) and fix to support all Unicode characters (iOS) - with GPL or special commercial license options
- [litehelpers / Cordova-sqlite-evplus-legacy-attach-detach-free](https://github.com/litehelpers/Cordova-sqlite-evplus-legacy-attach-detach-free) - version with support for ATTACH, includes internal memory improvements to support