mysqli_stmt::prepare
mysqli_stmt_prepare
(PHP 5, PHP 7)
mysqli_stmt::prepare -- mysqli_stmt_prepare — Prepare an SQL statement for execution
Description
Object oriented style
public mysqli_stmt::prepare ( string $query ) : mixed
Procedural style
mysqli_stmt_prepare ( mysqli_stmt $stmt , string $query ) : bool
Prepares the SQL query pointed to by the null-terminated string query.
The parameter markers must be bound to application variables using mysqli_stmt_bind_param() and/or mysqli_stmt_bind_result() before executing the statement or fetching rows.
Note:
In the case where you pass a statement to mysqli_stmt_prepare() that is longer than
max_allowed_packet
of the server, the returned error codes are different depending on whether you are using MySQL Native Driver (mysqlnd
) or MySQL Client Library (libmysqlclient
). The behavior is as follows:
mysqlnd
on Linux returns an error code of 1153. The error message meansgot a packet bigger than.max_allowed_packet
bytes
mysqlnd
on Windows returns an error code 2006. This error message meansserver has gone away.
libmysqlclient
on all platforms returns an error code 2006. This error message meansserver has gone away.
Parameters
-
stmt
-
Procedural style only: A statement identifier returned by mysqli_stmt_init().
-
query
-
The query, as a string. It must consist of a single SQL statement.
You can include one or more parameter markers in the SQL statement by embedding question mark (
?
) characters at the appropriate positions.Note:
You should not add a terminating semicolon or
\g
to the statement.Note:
The markers are legal only in certain places in SQL statements. For example, they are allowed in the VALUES() list of an INSERT statement (to specify column values for a row), or in a comparison with a column in a WHERE clause to specify a comparison value.
However, they are not allowed for identifiers (such as table or column names), in the select list that names the columns to be returned by a SELECT statement), or to specify both operands of a binary operator such as the
=
equal sign. The latter restriction is necessary because it would be impossible to determine the parameter type. In general, parameters are legal only in Data Manipulation Language (DML) statements, and not in Data Definition Language (DDL) statements.
Return Values
Returns true
on success or false
on failure.
Examples
Example #1 Object oriented style
<?php $mysqli = new mysqli("localhost", "my_user", "my_password", "world"); /* check connection */ if (mysqli_connect_errno()) { printf("Connect failed: %s\n", mysqli_connect_error()); exit(); } $city = "Amersfoort"; /* create a prepared statement */ $stmt = $mysqli->stmt_init(); if ($stmt->prepare("SELECT District FROM City WHERE Name=?")) { /* bind parameters for markers */ $stmt->bind_param("s", $city); /* execute query */ $stmt->execute(); /* bind result variables */ $stmt->bind_result($district); /* fetch value */ $stmt->fetch(); printf("%s is in district %s\n", $city, $district); /* close statement */ $stmt->close(); } /* close connection */ $mysqli->close(); ?>
Example #2 Procedural style
<?php $link = mysqli_connect("localhost", "my_user", "my_password", "world"); /* check connection */ if (mysqli_connect_errno()) { printf("Connect failed: %s\n", mysqli_connect_error()); exit(); } $city = "Amersfoort"; /* create a prepared statement */ $stmt = mysqli_stmt_init($link); if (mysqli_stmt_prepare($stmt, 'SELECT District FROM City WHERE Name=?')) { /* bind parameters for markers */ mysqli_stmt_bind_param($stmt, "s", $city); /* execute query */ mysqli_stmt_execute($stmt); /* bind result variables */ mysqli_stmt_bind_result($stmt, $district); /* fetch value */ mysqli_stmt_fetch($stmt); printf("%s is in district %s\n", $city, $district); /* close statement */ mysqli_stmt_close($stmt); } /* close connection */ mysqli_close($link); ?>
The above examples will output:
Amersfoort is in district Utrecht
See Also
- mysqli_stmt_init() - Initializes a statement and returns an object for use with mysqli_stmt_prepare
- mysqli_stmt_execute() - Executes a prepared Query
- mysqli_stmt_fetch() - Fetch results from a prepared statement into the bound variables
- mysqli_stmt_bind_param() - Binds variables to a prepared statement as parameters
- mysqli_stmt_bind_result() - Binds variables to a prepared statement for result storage
- mysqli_stmt_get_result() - Gets a result set from a prepared statement
- mysqli_stmt_close() - Closes a prepared statement
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/mysqli-stmt.prepare.php