FLUSH statement
Use the FLUSH statement to force rows that a PUT statement buffered to be written to the database.
Syntax
FLUSH
{
cursor_id
| cursor_id_var
}
| Element | Description | Restrictions | Syntax |
|---|---|---|---|
| cursor_id | Name of a cursor | Must have been declared | Identifier |
| cursor_id_var | Host variable that holds the value of cursor_id | Must be a character data type | Language specific |
Usage
Use this statement, which is an extension to the ANSI/ISO standard for SQL, with Informix® ESQL/C.
The PUT statement adds a row to a buffer, whose content is written to the database when the buffer is full. Use the FLUSH statement to force the insertion when the buffer is not full.
If the program terminates
without closing the cursor, the buffer is left unflushed. Rows placed
into the buffer since the last flush are lost. Do not expect the end
of the program to close the cursor and flush the buffer automatically.
The following example shows a FLUSH statement that operates on a cursor
called icurs:
FLUSH icurs Example
The
following example assumes that a function named next_cust returns
either information about a new customer or null data to signal the
end of input:
EXEC SQL BEGIN WORK;
EXEC SQL OPEN new_custs;
while(SQLCODE == 0)
{
next_cust();
if(the_company == NULL)
break;
EXEC SQL PUT new_custs;
}
if(SQLCODE == 0) /* if no problem with PUT */
{
EXEC SQL FLUSH new_custs;
/* write any rows left */
if(SQLCODE == 0) /* if no problem with FLUSH */
EXEC SQL COMMIT WORK; /* commit changes */
}
else
EXEC SQL ROLLBACK WORK; /* else undo changes */