SQL Server 2008 -- Table-Valued Parameter (3)

●TVP Limitations

1.TVPs are read-only after they are initially populated and passed; they cannot be used to return data.

2.The READONLY keyword must be applied to TVPs in the signatures of your stored procedures, or they will not compile.

3.Cannot update the column values in the rows of a TVP, and you cannot insert or delete rows. If you must modify the data in a TVP, one workaround is to insert the data from the TVP into a temporary table or into a table variable to which you can then apply changes.

4.There is no ALTER TABLE...AS TYPE statement that supports changing the schema of a TVP table type. Instead, you must first drop all stored procedures that reference the type before dropping the type, re-creating it with a new schema, and then re-creating the stored procedures.

5.Indexing is limited as well, with support only for PRIMARY KEY and UNIQUE constraints. Also, statistics on TVPs are not maintained by SQL Server.