Question: When will Table valued SQL UDFs be supported?
Private Answer: It is being considered for the next release.
Question: Next release… meaning 15.0.3 or v16?
Private Answer: Under consideration for 15.0.3
Question: is there a maximum limit on the size of the text in the sql udf?
Private Answer: The same as sql procedures. I don’t remember if there is any.
Question: Any plans on startup triggers (triggers to fire on ASE startup)?
Answer: There are no current plans for ASE startup triggers.
Question: is there a size limit on the return value from the udf?
Private Answer: We cannot return text/image.
According to the Targeted ASE 15.0 Release Schedule, we should see Sybase ASE v15.0.2 by the end of the month so it shouldn’t be too long before we will be able to play with the SQL User Defined Functions and the Instead Of Triggers.
More importantly, in fact, I think this is the most important feature of v15.0.2 is row level locking for system tables:
Earlier versions of Adaptive Server used exclusive table locks on system tables. The set of system tables Adaptive Server locked depended on the type of DDL operation you executed. If another DDL tried to take a conflicting exclusive table lock on the same system table, it had to wait to acquire the lock on any system catalogs. These DDL operations were executed serially.
This system impedes performance in temporary databases because their DDL activity is very high compared to regular database, which means their catalog contention is very high. This can limit the Adaptive Server throughput for applications that work with temporary tables.
The row-locked system tables allow the concurrent execution of DDL commands by using the row level locking infrastructure. Adaptive Server release 15.0.2 uses row-level locking to resolve these issues:
- System table contention, which was a bottleneck for many DDLs and utilities.
- tempdb contention. Because the system tables are locked at the row level, Adaptive Server 15.0.2 elimiates tempdb contention.
- Shared or exclusive table-level locks. Adaptive Server takes intent locks on catalogs only, which removes potential contention.
- Shared or exclusive table-level locks while executing DDLs and utilities. Adaptive Server 15.0 converted most of the system tables to DOL, but still took shared or exclusive table-level locks while executing DDLs and utilities. Using row-level locks for system tables eliminates this contention.
- DDLs and utilities blocking each other. Adaptive Server 15.0.2 allows DDLs and utilities to run in parallel.
Eventually this techcast will show up on Sybase’s TechCast Listing.