# pg_send_prepare

(PHP 5 >= 5.1.0, PHP 7)

pg_send_prepare — Sends a request to create a prepared statement with the given parameters, without waiting for completion

### 说明

pg_send_prepare ( resource `$connection` , string `$stmtname` , string `$query` ) : bool

Sends a request to create a prepared statement with the given parameters, without waiting for completion.

This is an asynchronous version of pg_prepare(): it returns `TRUE` if it was able to dispatch the request, and `FALSE` if not. After a successful call, call pg_get_result() to determine whether the server successfully created the prepared statement. The function's parameters are handled identically to pg_prepare(). Like pg_prepare(), it will not work on pre-7.4 versions of PostgreSQL.

### 参数

`connection`

  PostgreSQL database connection resource. When `connection` is not present, the default connection is used. The default connection is the last connection made by pg_connect() or pg_pconnect().

`stmtname`

  The name to give the prepared statement. Must be unique per-connection. If "" is specified, then an unnamed statement is created, overwriting any previously defined unnamed statement.

`query`

  The parameterized SQL statement. Must contain only a single statement. (multiple statements separated by semi-colons are not allowed.) If any parameters are used, they are referred to as $1, $2, etc.

### 返回值

Returns `TRUE` on success, `FALSE` on failure. Use pg_get_result() to determine the query result.

### 范例

Example #1 Using pg_send_prepare()

    <?php
      $dbconn = pg_connect("dbname=publisher") or die("Could not connect");

      // Prepare a query for execution
      if (!pg_connection_busy($dbconn)) {
        pg_send_prepare($dbconn, "my_query", 'SELECT * FROM shops WHERE name = $1');
        $res1 = pg_get_result($dbconn);
      }

      // Execute the prepared query.  Note that it is not necessary to escape
      // the string "Joe's Widgets" in any way
      if (!pg_connection_busy($dbconn)) {
        pg_send_execute($dbconn, "my_query", array("Joe's Widgets"));
        $res2 = pg_get_result($dbconn);
      }

      // Execute the same prepared query, this time with a different parameter
      if (!pg_connection_busy($dbconn)) {
        pg_send_execute($dbconn, "my_query", array("Clothes Clothes Clothes"));
        $res3 = pg_get_result($dbconn);
      }

    ?>

### 参见

- pg_connect() - 打开一个 PostgreSQL 连接
- pg_pconnect() - 打开一个持久的 PostgreSQL 连接
- pg_execute() - Sends a request to execute a prepared statement with given parameters, and waits for the result
- pg_send_execute() - Sends a request to execute a prepared statement with given parameters, without waiting for the result(s)
- pg_send_query_params() - Submits a command and separate parameters to the server without waiting for the result(s)