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"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.HandleEmptyInListsPlugin = void 0; const handle_empty_in_lists_transformer_js_1 = require("./handle-empty-in-lists-transformer.js"); /** * A plugin that allows handling `in ()` and `not in ()` expressions. * * These expressions are invalid SQL syntax for many databases, and result in runtime * database errors. * * The workarounds used by other libraries always involve modifying the query under * the hood, which is not aligned with Kysely's philosophy of WYSIWYG. We recommend manually checking * for empty arrays before passing them as arguments to `in` and `not in` expressions * instead, but understand that this can be cumbersome. Hence we're going with an * opt-in approach where you can choose if and how to handle these cases. We do * not want to make this the default behavior, as it can lead to unexpected behavior. * Use it at your own risk. Test it. Make sure it works as expected for you. * * Using this plugin also allows you to throw an error (thus avoiding unnecessary * requests to the database) or print a warning in these cases. * * ### Examples * * The following strategy replaces the `in`/`not in` expression with a noncontingent * expression. A contradiction (falsy) `1 = 0` for `in`, and a tautology (truthy) `1 = 1` for `not in`), * similarily to how {@link https://github.com/knex/knex/blob/176151d8048b2a7feeb89a3d649a5580786d4f4e/docs/src/guide/query-builder.md#L1763 | Knex.js}, * {@link https://github.com/prisma/prisma-engines/blob/99168c54187178484dae45d9478aa40cfd1866d2/quaint/src/visitor.rs#L804-L823 | PrismaORM}, * {@link https://github.com/laravel/framework/blob/8.x/src/Illuminate/Database/Query/Grammars/Grammar.php#L284-L291 | Laravel}, * {@link https://docs.sqlalchemy.org/en/13/core/engines.html#sqlalchemy.create_engine.params.empty_in_strategy | SQLAlchemy} * handle this. * * ```ts * import Sqlite from 'better-sqlite3' * import { * HandleEmptyInListsPlugin, * Kysely, * replaceWithNoncontingentExpression, * SqliteDialect, * } from 'kysely' * import type { Database } from 'type-editor' // imaginary module * * const db = new Kysely<Database>({ * dialect: new SqliteDialect({ * database: new Sqlite(':memory:'), * }), * plugins: [ * new HandleEmptyInListsPlugin({ * strategy: replaceWithNoncontingentExpression * }) * ], * }) * * const results = await db * .selectFrom('person') * .where('id', 'in', []) * .where('first_name', 'not in', []) * .selectAll() * .execute() * ``` * * The generated SQL (SQLite): * * ```sql * select * from "person" where 1 = 0 and 1 = 1 * ``` * * The following strategy does the following: * * When `in`, pushes a `null` value into the empty list resulting in `in (null)`, * similiarly to how {@link https://github.com/typeorm/typeorm/blob/0280cdc451c35ef73c830eb1191c95d34f6ce06e/src/query-builder/QueryBuilder.ts#L919-L922 | TypeORM} * and {@link https://github.com/sequelize/sequelize/blob/0f2891c6897e12bf9bf56df344aae5b698f58c7d/packages/core/src/abstract-dialect/where-sql-builder.ts#L368-L379 | Sequelize} * handle `in ()`. `in (null)` is logically the equivalent of `= null`, which returns * `null`, which is a falsy expression in most SQL databases. We recommend NOT * using this strategy if you plan to use `in` in `select`, `returning`, or `output` * clauses, as the return type differs from the `SqlBool` default type for comparisons. * * When `not in`, casts the left operand as `char` and pushes a unique value into * the empty list resulting in `cast({{lhs}} as char) not in ({{VALUE}})`. Casting * is required to avoid database errors with non-string values. * * ```ts * import Sqlite from 'better-sqlite3' * import { * HandleEmptyInListsPlugin, * Kysely, * pushValueIntoList, * SqliteDialect * } from 'kysely' * import type { Database } from 'type-editor' // imaginary module * * const db = new Kysely<Database>({ * dialect: new SqliteDialect({ * database: new Sqlite(':memory:'), * }), * plugins: [ * new HandleEmptyInListsPlugin({ * strategy: pushValueIntoList('__kysely_no_values_were_provided__') // choose a unique value for not in. has to be something with zero chance being in the data. * }) * ], * }) * * const results = await db * .selectFrom('person') * .where('id', 'in', []) * .where('first_name', 'not in', []) * .selectAll() * .execute() * ``` * * The generated SQL (SQLite): * * ```sql * select * from "person" where "id" in (null) and cast("first_name" as char) not in ('__kysely_no_values_were_provided__') * ``` * * The following custom strategy throws an error when an empty list is encountered * to avoid unnecessary requests to the database: * * ```ts * import Sqlite from 'better-sqlite3' * import { * HandleEmptyInListsPlugin, * Kysely, * SqliteDialect * } from 'kysely' * import type { Database } from 'type-editor' // imaginary module * * const db = new Kysely<Database>({ * dialect: new SqliteDialect({ * database: new Sqlite(':memory:'), * }), * plugins: [ * new HandleEmptyInListsPlugin({ * strategy: () => { * throw new Error('Empty in/not-in is not allowed') * } * }) * ], * }) * * const results = await db * .selectFrom('person') * .where('id', 'in', []) * .selectAll() * .execute() // throws an error with 'Empty in/not-in is not allowed' message! * ``` */ class HandleEmptyInListsPlugin { opt; #transformer; constructor(opt) { this.opt = opt; this.#transformer = new handle_empty_in_lists_transformer_js_1.HandleEmptyInListsTransformer(opt.strategy); } transformQuery(args) { return this.#transformer.transformNode(args.node, args.queryId); } async transformResult(args) { return args.result; } } exports.HandleEmptyInListsPlugin = HandleEmptyInListsPlugin;