compare null column with some other data, you shall give assumption value through one function command, For example If you want to write
as If record-id = 1 then
In this case if record-id value is null then this comparison fails instead of that the following syntax may be used "if NVL(record_id, 0 ) 1 then". Here NVL function takes a role if the given parameter or column value is null or no data found then that may be replaced as zero,
Hence NVL( ) is function which will accept two parameters such as column name, field name, variable name, separated by comma and then the required default value may be given as second parameters,
:NEW, On seeing the word, we shall expect :OLD, Also, Generally :NEW, Followed by column name will indicate, new value of column name and
:OLD,column name refers to old value available in the data storage,
For example, there is Pay as column name in a table and on particular record it has got 1200, On editing user has replaced this value with 1500,
:OLD.PAY → 1200
:NEW,PAY → 1500
another instance: at the time fresh record or on new insert, initial value may be null and then substituted value may be user's value
:OLD,PAY → null
:NEW,PAY → 1200
On this Before Insert Trigger with respect to Raak-Ledger-Master, we have one more requirement such as
→ Even if user enters ledger-name in lower case letters should be converted as upper case letters, Changes may be made on new record and