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3.8.36mysqli::prepare,mysqli_prepare

Copyright 1997-2022 the PHP Documentation Group.

  • mysqli::prepare

    mysqli_prepare

    Prepares an SQL statement for execution

Description

Object oriented style

publicmysqli_stmt|falsemysqli::prepare(stringquery);

Procedural style

mysqli_stmt|falsemysqli_prepare(mysqlimysql,
stringquery);

Prepares the SQL query, and returns a statement handle to be used for further operations on the statement. The query must consist of a single SQL statement.

The statement template can contain zero or more question mark (?) parameter markers⁠—also called placeholders. The parameter markers must be bound to application variables usingmysqli_stmt_bind_parambefore executing the statement.

Parameters

link

Procedural style only: A link identifier returned bymysqli_connectormysqli_init

query

The query, as a string. It must consist of a single SQL statement.

The SQL statement may contain zero or more parameter markers represented by question mark (?) characters at the appropriate positions.

Note

平方的标记只在某些地方是合法的L statements. For example, they are permitted in theVALUES()list of anINSERTstatement (to specify column values for a row), or in a comparison with a column in aWHEREclause to specify a comparison value.

However, they are not permitted for identifiers (such as table or column names), 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

mysqli_preparereturns a statement object orfalseif an error occurred.

Examples

Example 3.58mysqli::prepareexample

Object oriented style

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);

Procedural style

The above examples will output:

Amersfoort is in district Utrecht

See Also

mysqli_stmt_execute
mysqli_stmt_fetch
mysqli_stmt_bind_param
mysqli_stmt_bind_result
mysqli_stmt_get_result
mysqli_stmt_close