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@mysql/xdevapi

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MySQL Connector/Node.js - A Node.js driver for MySQL using the X Protocol and X DevAPI.

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/* * Copyright (c) 2015, 2022, Oracle and/or its affiliates. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License, version 2.0, as * published by the Free Software Foundation. * * This program is also distributed with certain software (including * but not limited to OpenSSL) that is licensed under separate terms, * as designated in a particular file or component or in included license * documentation. The authors of MySQL hereby grant you an * additional permission to link the program and your derivative works * with the separately licensed software that they have included with * MySQL. * * Without limiting anything contained in the foregoing, this file, * which is part of MySQL Connector/Node.js, is also subject to the * Universal FOSS Exception, version 1.0, a copy of which can be found at * http://oss.oracle.com/licenses/universal-foss-exception. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License, version 2.0, for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ 'use strict'; const Binding = require('./Binding'); const ColumnWrapper = require('./Util/columnWrapper'); const Filtering = require('./TableFiltering'); const Grouping = require('./Grouping'); const Locking = require('./Locking'); const Preparing = require('./Preparing'); const Projecting = require('./Projecting'); const Query = require('./Query'); const Result = require('./RowResult'); const Skipping = require('./Skipping'); const Ordering = require('./TableOrdering'); const dataModel = require('../Protocol/Stubs/mysqlx_crud_pb').DataModel.TABLE; /** * Factory function that creates an instance of a statement to search * for records in a table. * @module TableSelect * @mixes Binding * @mixes Grouping * @mixes Locking * @mixes Skipping * @mixes TableFiltering * @mixes TableOrdering * @see {@link https://dev.mysql.com/doc/x-devapi-userguide/en/crud-ebnf-table-crud-functions.html#crud-ebnf-tableselectfunction|TableSelectFunction} */ /** * @private * @alias module:TableSelect * @param {module:Connection} connection - The instance of the current * database connection. * @param {ExpressionTree[]} [projectionList] - A list containing object * representations of X DevAPI projected expression instances, which * establish the column names and aliases to include in the result set * when searching for records in the table. * @param {module:Schema} schema - The instance of the schema where the * statement is being executed. * @param {string} tableName - The name of the table where the statement is * being executed. * @returns {module:TableSelect} */ function TableSelect ({ connection, projectionList = [], schema, tableName } = {}) { // A TableSelect statement can be prepared, so it needs to provide // the appropriate capabilities and API. let preparable = Preparing({ connection }); // The TableSelect API is composed of multiple mixins that, each one, // introduce specific aspects and capabilities of the statement. preparable = { ...Binding(), ...Filtering({ preparable }), ...Grouping({ dataModel, preparable }), ...Locking({ preparable }), ...Ordering({ preparable }), ...Projecting({ projectionList }), ...Query({ category: dataModel, schema, tableName }), ...Skipping({ preparable }), ...preparable }; // The TableSelect API also introduces its own specific API. return { ...preparable, /** * Push-based cursor type used to iterate over rows in a result set * returned when searching for records in a table. * @callback module:TableSelect~rowCursor * @param {Array.<*>} items - The list of column values for the row in * the current cursor position. */ /** * Push-based cursor type used to iterate over the column metadata in * a result set returned when searching for records in a table. * @callback module:TableSelect~metadataCursor * @param {Array.<Object>} metadata - The list of objects containing * metadata details for each column. */ /** * Executes the statement in the database that searches for all * records in the table that match the given criteria. * If a push-based cursor is provided, it should be used to iterate * over the rows in result set. Additionally, if a metadata cursor * is also provided, it should be used to iterate over each column * definition. * @function * @name module:TableSelect#execute * @param {module:TableSelect~rowCursor} [dataCursor] - Callback * function that works as push-based cursor to iterate over the result * set. * @param {module:TableSelect~metadataCursor} [metadataCursor] - * Callback function that works as push-based cursor to iterate over * each column that contains values in the result set. * @return {Promise.<module:RowResult>} A <code>Promise</code> that * resolves to an object containing the result set returned by the * statement and any other detail reported by the server. If a * push-based cursor is provided, the result set will be empty. */ execute (dataCursor, metadataCursor) { // Before trying to send any message to the server, we need to // check if the connection is open (has a client instance) or if // it became idle in the meantime. if (!connection.isOpen() || connection.isIdle()) { // There is always a default error (ER_DEVAPI_CONNECTION_CLOSED). return Promise.reject(connection.getError()); } const integerType = connection.getIntegerType(); // In DOCUMENT mode, the result set is composed by the values of // every projected column, which are available as a JavaScript // array that corresponds to the row list. const cursor = dataCursor ? row => dataCursor(row?.toArray({ integerType })) : undefined; const fn = () => connection.getClient().crudFind(this, cursor, ColumnWrapper(metadataCursor)); return preparable.execute(fn, cursor, ColumnWrapper(metadataCursor)) .then(details => Result({ ...details, integerType })); } }; } module.exports = TableSelect;