dbTableDelete

function

Library: Database access (OMDB legacy)
Include: omdb.xin

Declaration

define external function dbTableDelete
       value    dbTable  table
 where value    stream   condition

Argument definitions

table: is an open dbTable object.

condition: is a condition to limit the number of rows deleted.

Purpose

Use dbTableDelete to delete records from a table using the supplied criteria.

Requirements

You must include the following line at the beginning of your OmniMark program:

  include "omdb.xin"

The condition must be

valid SQL (else external exception OMDB501) or
the specially defined constant DB_ALL_RECORDS (all records in the table will be removed).

Usage Notes

None.

Example

The following example uses dbTableDelete to remove grade references for students who did not finish a course. The deletion is performed through the dbTable OMX component.

  
  process
  
      ;  local variables
      local dbDatabase this-db
      local dbTable student-course
      ;  create the database OMX objects
      set this-db to dbOpenODBC 'dbDemo'
      set student-course to dbTableOpen this-db table 'StudentCourse'
  
      ;  drop students who did not finish from course lists
      dbTableDelete student-course where "Grade is NULL"
  
      ;  catch the database exceptions
      catch #external-exception identity catch-id message catch-msg
          output 'An error occurred while accessing an omDB function.%n'
          output '%g(catch-id)  :  %g(catch-msg)%n'