int mysql_stmt_prepare(MYSQL_STMT *stmt, const char
*stmt_str, unsigned long length)
Given the statement handle returned by
mysql_stmt_init(), prepares the
SQL statement pointed to by the string
stmt_str and returns a status value. The
string length should be given by the
argument. The string must consist of a single SQL statement. You
should not add a terminating semicolon
to the statement.
The application can include one or more parameter markers in the
SQL statement by embedding question mark
?”) characters into the SQL
string at the appropriate positions.
The markers are legal only in certain places in SQL statements.
For example, they are allowed in the
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), 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)
The parameter markers must be bound to application variables
before executing the statement.
Metadata changes to tables or views referred to by prepared statements are detected and cause automatic repreparation of the statement when it is next executed. For more information, see Section 12.6.4, “Automatic Prepared Statement Repreparation”.
Zero if the statement was prepared successfully. Nonzero if an error occurred.