Oracle 5.0 Reference Manual page 2219

If you obtained a
mysql_stmt_result_metadata(), you should also free the metadata using
mysql_free_result().
Execution Steps
To prepare and execute a statement, an application follows these steps:
1. Create a prepared statement handle with mysql_stmt_init(). To prepare the statement on the
server, call
2. If the statement will produce a result set, call
result set metadata. This metadata is itself in the form of result set, albeit a separate one from the
one that contains the rows returned by the query. The metadata result set indicates how many
columns are in the result and contains information about each column.
3. Set the values of any parameters using mysql_stmt_bind_param(). All parameters must be
set. Otherwise, statement execution returns an error or produces unexpected results.
4. Call
mysql_stmt_execute()
5. If the statement produces a result set, bind the data buffers to use for retrieving the row values by
calling mysql_stmt_bind_result().
6. Fetch the data into the buffers row by row by calling
more rows are found.
7. Repeat steps 3 through 6 as necessary, by changing the parameter values and re-executing the
statement.
When
mysql_stmt_prepare()
• The server parses the statement and sends the okay status back to the client by assigning a
statement ID. It also sends total number of parameters, a column count, and its metadata if it is a
result set oriented statement. All syntax and semantics of the statement are checked by the server
during this call.
• The client uses this statement ID for the further operations, so that the server can identify the
statement from among its pool of statements.
When
mysql_stmt_execute()
• The client uses the statement handle and sends the parameter data to the server.
• The server identifies the statement using the ID provided by the client, replaces the parameter
markers with the newly supplied data, and executes the statement. If the statement produces a result
set, the server sends the data back to the client. Otherwise, it sends an okay status and the number
of rows changed, deleted, or inserted.
When
mysql_stmt_fetch()
• The client reads the data from the current row of the result set and places it into the application data
buffers by doing the necessary conversions. If the application buffer type is same as that of the field
type returned from the server, the conversions are straightforward.
If an error occurs, you can get the statement error number, error message, and SQLSTATE code using
mysql_stmt_errno(), mysql_stmt_error(), and mysql_stmt_sqlstate(), respectively.
Prepared Statement Logging
For prepared statements that are executed with the
mysql_stmt_execute()
general query log so that you can tell when statements are prepared and executed.
C API Prepared Statement Function Overview
statement's result set metadata by calling
SELECT
mysql_stmt_prepare()
to execute the statement.
is called, the MySQL client/server protocol performs these actions:
is called, the MySQL client/server protocol performs these actions:
is called, the MySQL client/server protocol performs these actions:
C API functions, the server writes
and pass it a string containing the SQL statement.
mysql_stmt_result_metadata()
mysql_stmt_fetch()
mysql_stmt_prepare()
Prepare
2199
to obtain the
repeatedly until no
and
and lines to the
Execute