RETURNING Example (DSQL)
UPDATE Scholars
SET firstname = 'Hugh', lastname = 'Pickering'
WHERE firstname = 'Henry' and lastname = 'Higgins'
RETURNING id, old.lastname, new.lastname;
UPDATE Scholars
SET firstname = 'Hugh', lastname = 'Pickering'
WHERE firstname = 'Henry' and lastname = 'Higgins'
RETURNING id, old.lastname, new.lastname;
BLOB
columnsUpdating a BLOB
column always replaces the entire contents.Even the BLOB
ID, the “handle” that is stored directly in the column, is changed.BLOB
s can be updated if:
The client application has made special provisions for this operation, using the Firebird API.In this case, the modus operandi is application-specific and outside the scope of this manual.
The new value is a string literal of no more than 65,533 bytes (64KB - 3).
Note
|
A limit, in characters, is calculated at run-time for strings that are in multi-byte character sets, to avoid overrunning the bytes limit.For example, for a UTF8 string (max. 4 bytes/character), the run-time limit is likely to be about (floor(65533/4)) = 16383 characters. |
The source is itself a BLOB
column or, more generally, an expression that returns a BLOB
.
You use the INSERT CURSOR
statement (ESQL only).