Parameters
| cdp | client context variable |
| level | context level |
| itype | type of the returned context |
| par1 | basic part of the returned context, usually the number of the object, that experienced an error (the absolute value in the system table of tables or objects) |
| par2 | additional part of the returned context, if any |
| par3 | additional part of the returned context, if any |
| par4 | additional part of the returned context, if any |
| objname | name of the object in par1 (only in SQL); if it's an object with local declaration (e.g. local declaration of a procedure), the |
Since version
7.0, SQL form since 8.1
Description
If this function is called after an error, it'll return the information about the error context. More information about errors and exception in SQL can be found here.
The level output parameter specifies the error context level. The function returns the smallest context for 0 and a wider context for higher values. If the level value is greater or equal to the defined number of context levels, the itype parameter will return 0 indicating that the higher levels don't need to be examined.
This function is often used in a loop for level values from 0 and above until itype returns 0.
The itype parameter returns the context type and the returned context type specifies the way of interpreting other parameters:
| itype | par1 | par2 | par3 | par4 |
| 1 - table | table number | record number or -1 | column number or 255 | multiattribute value number or 65535 |
| 2 - index | table number | ordinal number of the index | -- | -- |
| 3 - procedure | procedure number | -- | -- | -- |
| 4 - trigger | trigger number | -- | -- | -- |
| 5 - SQL command | -- | -- | -- | -- |
| 6 - lock | table number or -1 | record or page number | lock type | blocking user |
| 7 - compiling | -- | -- | -- | -- |
| 8 - record | table number | record number | -- | -- |
| 9 - index key | -- | -- | -- | -- |
| 0 - end | -- | -- | -- | -- |
The parameters designated with -- are not defined and are not interpreted.
The SQL variant of this function can be called not only when an error occurs (i.e. in a corresponding handler), but anywhere in a routine. Then function then doesn't get the error context, but may simulate e.g. the stack dump - see examples.
Function value
This function returns FALSE if successful, TRUE otherwise..
Example
PROCEDURE stack();
// displays the stack dump of routines into log
BEGIN
DECLARE level,tp,p1,p2,p3,p4 INT;
DECLARE routine_name CHAR(63);
SET level=0;
cycle: LOOP
CALL Get_server_error_context(level, tp, p1, p2, p3, p4, routine_name);
IF tp=0 THEN LEAVE cycle; END IF; // end
IF tp=3 THEN // display procedure name
CALL Log_write('Procedure '+routine_name);
ELSEIF tp=4 then // display trigger name
CALL Log_write('Trigger '+routine_name);
ELSE
CALL Log_write('Other type '+CAST(tp AS CHAR(4)));
END IF;
SET level=level+1;
END LOOP;
END
See