dataEvent_record_BeforeDeleteRowWithConcurrentAccess
Function called before deleting a row with concurrent access.
Syntax
PUBLIC FUNCTION dataEvent_record_BeforeDeleteRowWithConcurrentAccess(
p_dataT0 record-type)
RETURNS (INTEGER, STRING, record-type)
The function has one parameter:
p_dataT0
. This is aRECORD
containing a row of data. It is defined according to the structure of the database table.
- An integer specifying the
SQLCA.SQLCODE
error number. Codes are defined as constants in the libdbappSql and libdbappCore files in the libdbapp library. If the code is a negative number, an SQL error has occurred. The errors that are relevant in this function are shown in the table.Table 1. SQLCA.SQLCODE Description Constant Value Success ERROR_SUCCESS
0 Failure ERROR_FAILURE
-1 Concurrent access failure ERROR_CONCURRENT_ACCESS_FAILURE
-2 Concurrent access not found ERROR_CONCURRENT_ACCESS_NOTFOUND
-3 - A string is returned with the
SQLERRMESSAGE
error message. - record-type. This is a
RECORD
type defined according to the structure of the database table.
Usage
When you select the Before Delete Row With ConcurrentAccess property for the creation of the event, a function shell is created. Enter your code in the function.
This function is called before deleting a row in a database where access is concurrent and where a table can be locked. Use this function to perform some operation, typically a SQL operation, on another table. For example, you could write the row of data to a backup table before the row is deleted. This event is called before deleting a row in the database .
Example: BeforeDeleteRowWithConcurrentAccess
This example uses the Before Delete Row code event for the Account table in the OfficeStore demo.
The row of data referenced by the variable p_dataT0
is written to a backup
table. It is assumed that you have created the backup table for account before saving the row to
it.
PUBLIC FUNCTION dataEvent_recAccount_BeforeDeleteRowWithConcurrentAccess(p_dataT0 RECORD LIKE account.*)
RETURNS (INTEGER, STRING, RECORD LIKE account.*)
DEFINE errNo INTEGER
DEFINE errMsg STRING
DISPLAY "dataEvent_recAccount_BeforeDeleteRowWithConcurrentAccess (Row scope) is raised"
TRY
INSERT INTO account_backup VALUES (p_dataT0.*)
CATCH
DISPLAY "SQL ERROR: ", SQLCA.SQLCODE
LET errNo = ERROR_FAILURE
LET errMsg = " - BeforeDeleteRowWithConcurrentAccess failed to insert row in backup "
END TRY
DISPLAY "dataEvent_recAccount_BeforeDeleteRowWithConcurrentAccess (Row scope) is exited"
RETURN errNo, errMsg, p_dataT0.*
END FUNCTION