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   1 # Executing queries
   2
   3 ext/pq provides three means to execute queries against the PostgreSQL server:
   4
   5 * pq\Connection::exec()
   6   Simple plain execution of a query.
   7 * pq\Connection::execParams()
   8   Automatic prepare & execute of an unnamed statement.
   9 * pq\Connection::prepare() and pq\Statement::exec()
  10   Explicit prepare & execute of an named statement.
  11
  12
  13 ## Simple plain execution of a query
  14
  15 pq\Connection::exec() accepts a single argument, a ***query string***, containing a single or multiple SQL queries, separated by semi-colon.
  16
  17         <?php
  18         $result = $c->exec("SELECT 1*s,2*s,3*s FROM generate_series(1,3) s");
  19         ?>
  20
  21 An object of class pq\Result is returned on success. See [Fetching results](pq/Result/: Fetching Results) for details.
  22
  23 > ***NOTE:***
  24 > Only the last result will be returned, if the query string contains more than one SQL query.
  25
  26
  27 ## Automatic prepare & execute of an unnamed statement
  28
  29 pq\Connection::execParams() accepts a ***query string*** with a single SQL query as first argument, which will be prepared as an unnamed statement.
  30
  31 The second argument is an ***array of parameters*** to execute the prepared statement with.
  32
  33 If the third argument is present, an ***array with pg_type OIDs***, those types will be used for the parameters. See [Using types](pq/: Using Types) for details.
  34
  35         <?php
  36         $result = $c->execParams("SELECT int($1) * s, int($2) * s, int($3) * s FROM generate_series(1,3) s", array(1,2,3));
  37         ?>
  38
  39 An object of class pq\Result is returned on success. See [Fetching results](pq/Result/: Fetching Results) for details.
  40
  41
  42 ## Explicit prepare & execute of a named statement
  43
  44 pq\Connection::prepare() requires the ***statement name*** as string as first argument. This name is used later to refer to this prepared statement. See [Prepared statements](pq/: Prepared Statements) for details.
  45
  46 The second argument is a ***query string*** containing a single SQL query, which will be prepared on the server.
  47
  48 If the third argument is present, an ***array with pg_type OIDs***, those types will be used for the parameters. See [Using types](pq/: Using Types) for details.
  49
  50         <?php
  51
  52         $statement = $c->prepare("my_stm", "SELECT \$1::int*s,\$2::int*s,\$3::int*s FROM generate_series(1,3) s");
  53         $result = $statement->exec(array(1,2,3));
  54
  55         ?>
  56
  57 An object of class pq\Statement will be returned on success. See [Prepared statements](pq/: Prepared Statements) for details.