Value of empty string '' in INT column

[pwills]

INVOICE is type INT.
I was alarmed to discover that:

SELECT TICKET_ID FROM TICKET WHERE INVOICE = ''

returns all the rows where INVOICE is 0 and NOT where it is blank.

How ON EARTH do I retrieve all rows with blank INVOICE?

 

[tlbroadbent]

SQL does an implied conversion of empty string '' to 0 when comparing to an INT column. An INT column cannot contain an empty string. It can hold an integer value or be NULL. Change your statment to search for NULL values.

SELECT TICKET_ID FROM TICKET WHERE INVOICE IS NULL
Terry L. Broadbent - DBA
Computing Links:

http://tlbroadbent.home.attbi.com/prog.htm

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