Module 18: Query Triggers

Query Triggers

01. How you can obtain Query Information at Run Time?

We can use the following system variables and built-ins to obtain information about queries: 

a.  SYSTEM.MODE

b.  SYSTEM.LAST_QUERY

c.  GET_BLOCK_PROPERTY

d.  SET_BLOCK_PROPERTY

e.  GET_ITEM_PROPERTY

f.  SET_ITEM_PROPERTY

02. Define Pre-query Trigger and Post-query Trigger?

Pre-Query Trigger:

•  Defined at block level

•  Fires once, before query is performed

Post-Query Trigger:

•  Fires for each fetched record (except during array processing)

•  Use to populate non database items and calculate statistics