DataEvent_record_AfterUpdateRow

Function called after updating row.

Syntax

PUBLIC FUNCTION dataEvent_record_AfterUpdateRow(
   errNo INTEGER, 
   errMsg STRING, 
   uniqueKey record-type)
   RETURNS (INTEGER, STRING)

The function has these parameters:

  1. errNo. This is an SQLCA.SQLCODE error.
  2. errMsg. This is the SQLERRMESSAGE message.
  3. uniqueKey. This is a RECORD type defined in the BAM-generated common file (my_entity_common.4gl). It includes the unique key fields from the schema of the database table.
Returns values:
  1. 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
  2. A string is returned with the SQLERRMESSAGE error message.

Usage

When you select the After Update Row property for the creation of the event, a function shell is created. Enter your code in the function.

This function is called after updating a row in the database. Use this function to perform some operation, typically a SQL operation, on another table. For example, you could record details about the updated row of data in a log table.

Example: After Update Row

This example uses the After Update Row code event for the Account table in the OfficeStore demo.

In the example a row of data is written to a log table with a call to the function writeDataToLog.

The writeDataToLog function references two parameters:
  • The record that stores the row of data from the account table.
  • The operation type of the code event function in a reference to the relevant libdbappUI constant.
The parameters hold values written to the log table.
# AccountForm.4gl

-- import user-defined functions
IMPORT FGL myAccountFunc

PUBLIC FUNCTION dataEvent_recAccount_AfterUpdateRow(errNo INTEGER, errMsg STRING, 
                uniqueKey recAccount_br_uk_type)
    RETURNS (INTEGER, STRING)

    DEFINE l_data RECORD LIKE account.*
    
    DISPLAY "dataEvent_recAccount_AfterUpdateRow (Row scope) is raised"

    SELECT * INTO l_data.* FROM account WHERE @userid = uniqueKey.account_userid
    CALL myAccountFunc.writeDataToLog(l_data,libdbappUI.C_ACTION_UPDATE) RETURNING errNo
    IF errNo = libdbappCore.ERROR_FAILURE THEN
       LET errMsg = " - AfterUpdateRow failed to insert log " 
    END IF

    DISPLAY "dataEvent_recAccount_AfterUpdateRow (Row scope) is exited"

    RETURN errNo, errMsg
END FUNCTION

writeDataToLog

In this section there is an example of the function writeDataToLog called to write data to a log table.

It is assumed that you have created the log table before saving the row to it. The log table in the example has the following schema:
  • an "id" field that is auto incremented
  • a "date" timestamp field to record the date and time of the operation
  • a "type" field to record the operation (Update/Insert/Delete)
  • a "data" field to record a copy of all field values from the account table

All functions that you would reuse across forms and applications would reside in a module you create. To use these functions in your project, you would import your module into the entity module (for example, AccountForm.4gl) using the IMPORT FGL statement.

# MyAccountFunc.4gl

IMPORT FGL libdbappCore

FUNCTION writeDataToLog(dataRec RECORD LIKE account.*, opType INTEGER) 
  RETURNS (INTEGER)
  
  DEFINE errNo INTEGER
  DEFINE recLog RECORD LIKE log.*
  DEFINE t TEXT   
  
  LOCATE t IN MEMORY  
  LET recLog.id = NULL
  LET recLog.date = CURRENT  
  LET recLog.type = opType
  LET t = SFMT("id = %1 email = %2 firstname = %3 lastname = %4  acstatus = %5  addr1 = %6  
               addr2= %7 city = %8  state = %9 zip = %10 country = %11 phone = %12",
               dataRec.userid, dataRec.email, dataRec.firstname, dataRec.lastname,
               dataRec.acstatus, dataRec.addr1, dataRec.addr2, dataRec.city, dataRec.state,
               dataRec.zip, dataRec.country, dataRec.phone)  
  LET recLog.data = t
  TRY
     INSERT INTO log VALUES (recLog.*)
  CATCH
     DISPLAY "SQL ERROR: ", sqlca.sqlcode
     LET errNo = libdbappCore.ERROR_FAILURE
  END TRY
  RETURN errNo
 
END FUNCTION