Hi Ralf, I studied the documentation of 'TYPE 4 JDBC Driveer for sybase database'. It says the following
"When the Sybase driver establishes a connection, the driver sets the Sybase database option ansinull to on. Setting ansinull to on ensures that the driver is compliant with the ANSI SQL standard and is consistent with the behavior of other DataDirect Connect for JDBC drivers, which simplifies developing cross-database applications.
By default, Sybase does not evaluate NULL values in SQL equality (=) comparisons in an ANSI SQL-compliant manner. For example, the ANSI SQL specification defines that col1=null always evaluates to false. Using the default database setting (ansinull=off), if the value of col1 in the following statement is NULL, the comparison evaluates to true instead of false:
SELECT * FROM table WHERE col1 = NULL
Setting ansinull to on changes the default database behavior so that SQL statements must use IS NULL instead of =NULL. For example, using the Sybase driver, if the value of col1 in the following statement is NULL, the comparison evaluates to true:
SELECT * FROM table WHERE col1 IS NULL"
As mentioned above, this is an issue of ANSI SQL standard. As the JDBC driver is now making sure that the SYBASE should behave according to ANSI SQL standard, it means that 'is NULL' will work in sybase too. I didn't work on sybase at all so I cannot comment on whether old jdbc drivers supports that or not.
What do you comment?