mysql_unbuffered_query() sends a SQL query
query to MySQL, without fetching and
buffering the result rows automatically, as
mysql_query() does. On the one hand, this
saves a considerable amount of memory with SQL queries that
produce large result sets. On the other hand, you can start
working on the result set immediately after the first row has
been retrieved: you don't have to wait until the complete SQL
query has been performed. When using multiple DB-connects, you
have to specify the optional parameter
link_identifier.
Parameters
query
A SQL query
link_identifier
The MySQL connection. If the
link identifier is not specified, the last link opened by
mysql_connect() is assumed. If no such link is found, it
will try to create one as if mysql_connect() was called
with no arguments. If by chance no connection is found or established, an
E_WARNING level warning is generated.
Return Values
For SELECT, SHOW, DESCRIBE or EXPLAIN statements,
mysql_unbuffered_query()
returns a resource on success, or FALSE on
error.
For other type of SQL statements, UPDATE, DELETE, DROP, etc,
mysql_unbuffered_query() returns TRUE on success
or FALSE on error.
Notes
Note:
The benefits of mysql_unbuffered_query() come
at a cost: You cannot use mysql_num_rows() and
mysql_data_seek() on a result set returned from
mysql_unbuffered_query(). You also have to
fetch all result rows from an unbuffered SQL query, before you
can send a new SQL query to MySQL.
