Send more than one row
When you execute the INSERT statement, the statement sends
one row of data to the database server. When an INSERT statement sends
more than one row, define an insert cursor with the DECLARE
statement. An insert cursor enables you to buffer multiple rows of
data for insertion at one time. The DECLARE statement associates the
INSERT statement with the insert cursor. In the DECLARE statement,
the INSERT statement can be in either of the following formats:
- A literal INSERT statement in the DECLARE statement The following DECLARE statement associates a literal INSERT statement with the ins1_curs cursor:
EXEC SQL declare ins1_curs cursor for insert into customer values;
- A prepared INSERT statement in the DECLARE statement The following DECLARE statement associates a prepared INSERT statement with the ins2_curs cursor:
EXEC SQL prepare ins_stmt from 'insert into customer values'; EXEC SQL declare ins2_curs cursor for ins_stmt;
If you use an insert cursor it can be much more efficient
than if you insert rows one at a time, because the application process
does not need to send new rows to the database as often. You can use
a sequential or hold cursor for the insert cursor. The following table
summarizes the SQL statements that manage an insert cursor.
Task | Insert cursor |
---|---|
Declare the cursor ID | DECLARE associated with an INSERT statement |
Execute the statement | OPEN |
Send a single row from the program into the insert buffer | PUT |
Clear the insert buffer and send the contents to the database server | FLUSH |
Close the cursor | CLOSE |
Free cursor resources | FREE |
For more information about any of these statements, see their entries in the Informix® Guide to SQL: Syntax. You can change the size of the insert buffer with the Fetch-Buffer-Size feature. For more information, see Size the cursor buffer.