select('id, name') * ->from('user') * ->limit(10); * // build and execute the query * $rows = $query->all(); * // alternatively, you can create DB command and execute it * $command = $query->createCommand(); * // $command->sql returns the actual SQL * $rows = $command->queryAll(); * ``` * * @author Qiang Xue * @author Carsten Brandt * @since 2.0 */ class Query extends Component implements QueryInterface { use QueryTrait; /** * @var array the columns being selected. For example, `['id', 'name']`. * This is used to construct the SELECT clause in a SQL statement. If not set, it means selecting all columns. * @see select() */ public $select; /** * @var string additional option that should be appended to the 'SELECT' keyword. For example, * in MySQL, the option 'SQL_CALC_FOUND_ROWS' can be used. */ public $selectOption; /** * @var boolean whether to select distinct rows of data only. If this is set true, * the SELECT clause would be changed to SELECT DISTINCT. */ public $distinct; /** * @var array the table(s) to be selected from. For example, `['user', 'post']`. * This is used to construct the FROM clause in a SQL statement. * @see from() */ public $from; /** * @var array how to group the query results. For example, `['company', 'department']`. * This is used to construct the GROUP BY clause in a SQL statement. */ public $groupBy; /** * @var array how to join with other tables. Each array element represents the specification * of one join which has the following structure: * * ~~~ * [$joinType, $tableName, $joinCondition] * ~~~ * * For example, * * ~~~ * [ * ['INNER JOIN', 'user', 'user.id = author_id'], * ['LEFT JOIN', 'team', 'team.id = team_id'], * ] * ~~~ */ public $join; /** * @var string|array the condition to be applied in the GROUP BY clause. * It can be either a string or an array. Please refer to [[where()]] on how to specify the condition. */ public $having; /** * @var array this is used to construct the UNION clause(s) in a SQL statement. * Each array element is an array of the following structure: * * - `query`: either a string or a [[Query]] object representing a query * - `all`: boolean, whether it should be `UNION ALL` or `UNION` */ public $union; /** * @var array list of query parameter values indexed by parameter placeholders. * For example, `[':name' => 'Dan', ':age' => 31]`. */ public $params = []; /** * Creates a DB command that can be used to execute this query. * @param Connection $db the database connection used to generate the SQL statement. * If this parameter is not given, the `db` application component will be used. * @return Command the created DB command instance. */ public function createCommand($db = null) { if ($db === null) { $db = Yii::$app->getDb(); } list ($sql, $params) = $db->getQueryBuilder()->build($this); return $db->createCommand($sql, $params); } /** * Prepares for building SQL. * This method is called by [[QueryBuilder]] when it starts to build SQL from a query object. * You may override this method to do some final preparation work when converting a query into a SQL statement. * @param QueryBuilder $builder * @return Query a prepared query instance which will be used by [[QueryBuilder]] to build the SQL */ public function prepare($builder) { return $this; } /** * Starts a batch query. * * A batch query supports fetching data in batches, which can keep the memory usage under a limit. * This method will return a [[BatchQueryResult]] object which implements the [[\Iterator]] interface * and can be traversed to retrieve the data in batches. * * For example, * * ```php * $query = (new Query)->from('user'); * foreach ($query->batch() as $rows) { * // $rows is an array of 10 or fewer rows from user table * } * ``` * * @param integer $batchSize the number of records to be fetched in each batch. * @param Connection $db the database connection. If not set, the "db" application component will be used. * @return BatchQueryResult the batch query result. It implements the [[\Iterator]] interface * and can be traversed to retrieve the data in batches. */ public function batch($batchSize = 100, $db = null) { return Yii::createObject([ 'class' => BatchQueryResult::className(), 'query' => $this, 'batchSize' => $batchSize, 'db' => $db, 'each' => false, ]); } /** * Starts a batch query and retrieves data row by row. * This method is similar to [[batch()]] except that in each iteration of the result, * only one row of data is returned. For example, * * ```php * $query = (new Query)->from('user'); * foreach ($query->each() as $row) { * } * ``` * * @param integer $batchSize the number of records to be fetched in each batch. * @param Connection $db the database connection. If not set, the "db" application component will be used. * @return BatchQueryResult the batch query result. It implements the [[\Iterator]] interface * and can be traversed to retrieve the data in batches. */ public function each($batchSize = 100, $db = null) { return Yii::createObject([ 'class' => BatchQueryResult::className(), 'query' => $this, 'batchSize' => $batchSize, 'db' => $db, 'each' => true, ]); } /** * Executes the query and returns all results as an array. * @param Connection $db the database connection used to generate the SQL statement. * If this parameter is not given, the `db` application component will be used. * @return array the query results. If the query results in nothing, an empty array will be returned. */ public function all($db = null) { $rows = $this->createCommand($db)->queryAll(); return $this->populate($rows); } /** * Converts the raw query results into the format as specified by this query. * This method is internally used to convert the data fetched from database * into the format as required by this query. * @param array $rows the raw query result from database * @return array the converted query result */ public function populate($rows) { if ($this->indexBy === null) { return $rows; } $result = []; foreach ($rows as $row) { if (is_string($this->indexBy)) { $key = $row[$this->indexBy]; } else { $key = call_user_func($this->indexBy, $row); } $result[$key] = $row; } return $result; } /** * Executes the query and returns a single row of result. * @param Connection $db the database connection used to generate the SQL statement. * If this parameter is not given, the `db` application component will be used. * @return array|boolean the first row (in terms of an array) of the query result. False is returned if the query * results in nothing. */ public function one($db = null) { return $this->createCommand($db)->queryOne(); } /** * Returns the query result as a scalar value. * The value returned will be the first column in the first row of the query results. * @param Connection $db the database connection used to generate the SQL statement. * If this parameter is not given, the `db` application component will be used. * @return string|boolean the value of the first column in the first row of the query result. * False is returned if the query result is empty. */ public function scalar($db = null) { return $this->createCommand($db)->queryScalar(); } /** * Executes the query and returns the first column of the result. * @param Connection $db the database connection used to generate the SQL statement. * If this parameter is not given, the `db` application component will be used. * @return array the first column of the query result. An empty array is returned if the query results in nothing. */ public function column($db = null) { if (!is_string($this->indexBy)) { return $this->createCommand($db)->queryColumn(); } if (is_array($this->select) && count($this->select) === 1) { $this->select[] = $this->indexBy; } $rows = $this->createCommand($db)->queryAll(); $results = []; foreach ($rows as $row) { if (array_key_exists($this->indexBy, $row)) { $results[$row[$this->indexBy]] = reset($row); } else { $results[] = reset($row); } } return $results; } /** * Returns the number of records. * @param string $q the COUNT expression. Defaults to '*'. * Make sure you properly [quote](guide:db-dao#quoting-table-and-column-names) column names in the expression. * @param Connection $db the database connection used to generate the SQL statement. * If this parameter is not given (or null), the `db` application component will be used. * @return integer|string number of records. The result may be a string depending on the * underlying database engine and to support integer values higher than a 32bit PHP integer can handle. */ public function count($q = '*', $db = null) { return $this->queryScalar("COUNT($q)", $db); } /** * Returns the sum of the specified column values. * @param string $q the column name or expression. * Make sure you properly [quote](guide:db-dao#quoting-table-and-column-names) column names in the expression. * @param Connection $db the database connection used to generate the SQL statement. * If this parameter is not given, the `db` application component will be used. * @return mixed the sum of the specified column values. */ public function sum($q, $db = null) { return $this->queryScalar("SUM($q)", $db); } /** * Returns the average of the specified column values. * @param string $q the column name or expression. * Make sure you properly [quote](guide:db-dao#quoting-table-and-column-names) column names in the expression. * @param Connection $db the database connection used to generate the SQL statement. * If this parameter is not given, the `db` application component will be used. * @return mixed the average of the specified column values. */ public function average($q, $db = null) { return $this->queryScalar("AVG($q)", $db); } /** * Returns the minimum of the specified column values. * @param string $q the column name or expression. * Make sure you properly [quote](guide:db-dao#quoting-table-and-column-names) column names in the expression. * @param Connection $db the database connection used to generate the SQL statement. * If this parameter is not given, the `db` application component will be used. * @return mixed the minimum of the specified column values. */ public function min($q, $db = null) { return $this->queryScalar("MIN($q)", $db); } /** * Returns the maximum of the specified column values. * @param string $q the column name or expression. * Make sure you properly [quote](guide:db-dao#quoting-table-and-column-names) column names in the expression. * @param Connection $db the database connection used to generate the SQL statement. * If this parameter is not given, the `db` application component will be used. * @return mixed the maximum of the specified column values. */ public function max($q, $db = null) { return $this->queryScalar("MAX($q)", $db); } /** * Returns a value indicating whether the query result contains any row of data. * @param Connection $db the database connection used to generate the SQL statement. * If this parameter is not given, the `db` application component will be used. * @return boolean whether the query result contains any row of data. */ public function exists($db = null) { $select = $this->select; $this->select = [new Expression('1')]; $command = $this->createCommand($db); $this->select = $select; return $command->queryScalar() !== false; } /** * Queries a scalar value by setting [[select]] first. * Restores the value of select to make this query reusable. * @param string|Expression $selectExpression * @param Connection|null $db * @return bool|string */ protected function queryScalar($selectExpression, $db) { $select = $this->select; $limit = $this->limit; $offset = $this->offset; $this->select = [$selectExpression]; $this->limit = null; $this->offset = null; $command = $this->createCommand($db); $this->select = $select; $this->limit = $limit; $this->offset = $offset; if (empty($this->groupBy) && empty($this->having) && empty($this->union) && !$this->distinct) { return $command->queryScalar(); } else { return (new Query)->select([$selectExpression]) ->from(['c' => $this]) ->createCommand($command->db) ->queryScalar(); } } /** * Sets the SELECT part of the query. * @param string|array $columns the columns to be selected. * Columns can be specified in either a string (e.g. "id, name") or an array (e.g. ['id', 'name']). * Columns can be prefixed with table names (e.g. "user.id") and/or contain column aliases (e.g. "user.id AS user_id"). * The method will automatically quote the column names unless a column contains some parenthesis * (which means the column contains a DB expression). * * Note that if you are selecting an expression like `CONCAT(first_name, ' ', last_name)`, you should * use an array to specify the columns. Otherwise, the expression may be incorrectly split into several parts. * * When the columns are specified as an array, you may also use array keys as the column aliases (if a column * does not need alias, do not use a string key). * * Starting from version 2.0.1, you may also select sub-queries as columns by specifying each such column * as a `Query` instance representing the sub-query. * * @param string $option additional option that should be appended to the 'SELECT' keyword. For example, * in MySQL, the option 'SQL_CALC_FOUND_ROWS' can be used. * @return $this the query object itself */ public function select($columns, $option = null) { if (!is_array($columns)) { $columns = preg_split('/\s*,\s*/', trim($columns), -1, PREG_SPLIT_NO_EMPTY); } $this->select = $columns; $this->selectOption = $option; return $this; } /** * Add more columns to the SELECT part of the query. * * Note, that if [[select]] has not been specified before, you should include `*` explicitly * if you want to select all remaining columns too: * * ```php * $query->addSelect(["*", "CONCAT(first_name, ' ', last_name) AS full_name"])->one(); * ``` * * @param string|array $columns the columns to add to the select. * @return $this the query object itself * @see select() */ public function addSelect($columns) { if (!is_array($columns)) { $columns = preg_split('/\s*,\s*/', trim($columns), -1, PREG_SPLIT_NO_EMPTY); } if ($this->select === null) { $this->select = $columns; } else { $this->select = array_merge($this->select, $columns); } return $this; } /** * Sets the value indicating whether to SELECT DISTINCT or not. * @param boolean $value whether to SELECT DISTINCT or not. * @return $this the query object itself */ public function distinct($value = true) { $this->distinct = $value; return $this; } /** * Sets the FROM part of the query. * @param string|array $tables the table(s) to be selected from. This can be either a string (e.g. `'user'`) * or an array (e.g. `['user', 'profile']`) specifying one or several table names. * Table names can contain schema prefixes (e.g. `'public.user'`) and/or table aliases (e.g. `'user u'`). * The method will automatically quote the table names unless it contains some parenthesis * (which means the table is given as a sub-query or DB expression). * * When the tables are specified as an array, you may also use the array keys as the table aliases * (if a table does not need alias, do not use a string key). * * Use a Query object to represent a sub-query. In this case, the corresponding array key will be used * as the alias for the sub-query. * * @return $this the query object itself */ public function from($tables) { if (!is_array($tables)) { $tables = preg_split('/\s*,\s*/', trim($tables), -1, PREG_SPLIT_NO_EMPTY); } $this->from = $tables; return $this; } /** * Sets the WHERE part of the query. * * The method requires a `$condition` parameter, and optionally a `$params` parameter * specifying the values to be bound to the query. * * The `$condition` parameter should be either a string (e.g. `'id=1'`) or an array. * * @inheritdoc * * @param string|array $condition the conditions that should be put in the WHERE part. * @param array $params the parameters (name => value) to be bound to the query. * @return $this the query object itself * @see andWhere() * @see orWhere() * @see QueryInterface::where() */ public function where($condition, $params = []) { $this->where = $condition; $this->addParams($params); return $this; } /** * Adds an additional WHERE condition to the existing one. * The new condition and the existing one will be joined using the 'AND' operator. * @param string|array $condition the new WHERE condition. Please refer to [[where()]] * on how to specify this parameter. * @param array $params the parameters (name => value) to be bound to the query. * @return $this the query object itself * @see where() * @see orWhere() */ public function andWhere($condition, $params = []) { if ($this->where === null) { $this->where = $condition; } else { $this->where = ['and', $this->where, $condition]; } $this->addParams($params); return $this; } /** * Adds an additional WHERE condition to the existing one. * The new condition and the existing one will be joined using the 'OR' operator. * @param string|array $condition the new WHERE condition. Please refer to [[where()]] * on how to specify this parameter. * @param array $params the parameters (name => value) to be bound to the query. * @return $this the query object itself * @see where() * @see andWhere() */ public function orWhere($condition, $params = []) { if ($this->where === null) { $this->where = $condition; } else { $this->where = ['or', $this->where, $condition]; } $this->addParams($params); return $this; } /** * Appends a JOIN part to the query. * The first parameter specifies what type of join it is. * @param string $type the type of join, such as INNER JOIN, LEFT JOIN. * @param string|array $table the table to be joined. * * Use string to represent the name of the table to be joined. * Table name can contain schema prefix (e.g. 'public.user') and/or table alias (e.g. 'user u'). * The method will automatically quote the table name unless it contains some parenthesis * (which means the table is given as a sub-query or DB expression). * * Use array to represent joining with a sub-query. The array must contain only one element. * The value must be a Query object representing the sub-query while the corresponding key * represents the alias for the sub-query. * * @param string|array $on the join condition that should appear in the ON part. * Please refer to [[where()]] on how to specify this parameter. * @param array $params the parameters (name => value) to be bound to the query. * @return Query the query object itself */ public function join($type, $table, $on = '', $params = []) { $this->join[] = [$type, $table, $on]; return $this->addParams($params); } /** * Appends an INNER JOIN part to the query. * @param string|array $table the table to be joined. * * Use string to represent the name of the table to be joined. * Table name can contain schema prefix (e.g. 'public.user') and/or table alias (e.g. 'user u'). * The method will automatically quote the table name unless it contains some parenthesis * (which means the table is given as a sub-query or DB expression). * * Use array to represent joining with a sub-query. The array must contain only one element. * The value must be a Query object representing the sub-query while the corresponding key * represents the alias for the sub-query. * * @param string|array $on the join condition that should appear in the ON part. * Please refer to [[where()]] on how to specify this parameter. * @param array $params the parameters (name => value) to be bound to the query. * @return Query the query object itself */ public function innerJoin($table, $on = '', $params = []) { $this->join[] = ['INNER JOIN', $table, $on]; return $this->addParams($params); } /** * Appends a LEFT OUTER JOIN part to the query. * @param string|array $table the table to be joined. * * Use string to represent the name of the table to be joined. * Table name can contain schema prefix (e.g. 'public.user') and/or table alias (e.g. 'user u'). * The method will automatically quote the table name unless it contains some parenthesis * (which means the table is given as a sub-query or DB expression). * * Use array to represent joining with a sub-query. The array must contain only one element. * The value must be a Query object representing the sub-query while the corresponding key * represents the alias for the sub-query. * * @param string|array $on the join condition that should appear in the ON part. * Please refer to [[where()]] on how to specify this parameter. * @param array $params the parameters (name => value) to be bound to the query * @return Query the query object itself */ public function leftJoin($table, $on = '', $params = []) { $this->join[] = ['LEFT JOIN', $table, $on]; return $this->addParams($params); } /** * Appends a RIGHT OUTER JOIN part to the query. * @param string|array $table the table to be joined. * * Use string to represent the name of the table to be joined. * Table name can contain schema prefix (e.g. 'public.user') and/or table alias (e.g. 'user u'). * The method will automatically quote the table name unless it contains some parenthesis * (which means the table is given as a sub-query or DB expression). * * Use array to represent joining with a sub-query. The array must contain only one element. * The value must be a Query object representing the sub-query while the corresponding key * represents the alias for the sub-query. * * @param string|array $on the join condition that should appear in the ON part. * Please refer to [[where()]] on how to specify this parameter. * @param array $params the parameters (name => value) to be bound to the query * @return Query the query object itself */ public function rightJoin($table, $on = '', $params = []) { $this->join[] = ['RIGHT JOIN', $table, $on]; return $this->addParams($params); } /** * Sets the GROUP BY part of the query. * @param string|array $columns the columns to be grouped by. * Columns can be specified in either a string (e.g. "id, name") or an array (e.g. ['id', 'name']). * The method will automatically quote the column names unless a column contains some parenthesis * (which means the column contains a DB expression). * @return $this the query object itself * @see addGroupBy() */ public function groupBy($columns) { if (!is_array($columns)) { $columns = preg_split('/\s*,\s*/', trim($columns), -1, PREG_SPLIT_NO_EMPTY); } $this->groupBy = $columns; return $this; } /** * Adds additional group-by columns to the existing ones. * @param string|array $columns additional columns to be grouped by. * Columns can be specified in either a string (e.g. "id, name") or an array (e.g. ['id', 'name']). * The method will automatically quote the column names unless a column contains some parenthesis * (which means the column contains a DB expression). * @return $this the query object itself * @see groupBy() */ public function addGroupBy($columns) { if (!is_array($columns)) { $columns = preg_split('/\s*,\s*/', trim($columns), -1, PREG_SPLIT_NO_EMPTY); } if ($this->groupBy === null) { $this->groupBy = $columns; } else { $this->groupBy = array_merge($this->groupBy, $columns); } return $this; } /** * Sets the HAVING part of the query. * @param string|array $condition the conditions to be put after HAVING. * Please refer to [[where()]] on how to specify this parameter. * @param array $params the parameters (name => value) to be bound to the query. * @return $this the query object itself * @see andHaving() * @see orHaving() */ public function having($condition, $params = []) { $this->having = $condition; $this->addParams($params); return $this; } /** * Adds an additional HAVING condition to the existing one. * The new condition and the existing one will be joined using the 'AND' operator. * @param string|array $condition the new HAVING condition. Please refer to [[where()]] * on how to specify this parameter. * @param array $params the parameters (name => value) to be bound to the query. * @return $this the query object itself * @see having() * @see orHaving() */ public function andHaving($condition, $params = []) { if ($this->having === null) { $this->having = $condition; } else { $this->having = ['and', $this->having, $condition]; } $this->addParams($params); return $this; } /** * Adds an additional HAVING condition to the existing one. * The new condition and the existing one will be joined using the 'OR' operator. * @param string|array $condition the new HAVING condition. Please refer to [[where()]] * on how to specify this parameter. * @param array $params the parameters (name => value) to be bound to the query. * @return $this the query object itself * @see having() * @see andHaving() */ public function orHaving($condition, $params = []) { if ($this->having === null) { $this->having = $condition; } else { $this->having = ['or', $this->having, $condition]; } $this->addParams($params); return $this; } /** * Appends a SQL statement using UNION operator. * @param string|Query $sql the SQL statement to be appended using UNION * @param boolean $all TRUE if using UNION ALL and FALSE if using UNION * @return $this the query object itself */ public function union($sql, $all = false) { $this->union[] = ['query' => $sql, 'all' => $all]; return $this; } /** * Sets the parameters to be bound to the query. * @param array $params list of query parameter values indexed by parameter placeholders. * For example, `[':name' => 'Dan', ':age' => 31]`. * @return $this the query object itself * @see addParams() */ public function params($params) { $this->params = $params; return $this; } /** * Adds additional parameters to be bound to the query. * @param array $params list of query parameter values indexed by parameter placeholders. * For example, `[':name' => 'Dan', ':age' => 31]`. * @return $this the query object itself * @see params() */ public function addParams($params) { if (!empty($params)) { if (empty($this->params)) { $this->params = $params; } else { foreach ($params as $name => $value) { if (is_int($name)) { $this->params[] = $value; } else { $this->params[$name] = $value; } } } } return $this; } /** * Creates a new Query object and copies its property values from an existing one. * The properties being copies are the ones to be used by query builders. * @param Query $from the source query object * @return Query the new Query object */ public static function create($from) { return new self([ 'where' => $from->where, 'limit' => $from->limit, 'offset' => $from->offset, 'orderBy' => $from->orderBy, 'indexBy' => $from->indexBy, 'select' => $from->select, 'selectOption' => $from->selectOption, 'distinct' => $from->distinct, 'from' => $from->from, 'groupBy' => $from->groupBy, 'join' => $from->join, 'having' => $from->having, 'union' => $from->union, 'params' => $from->params, ]); } }