Creating and Using Inline Table-Valued Functions

Inline Table Valued Functions (iTVFs) are one type of user defined function that is available to implement in SQL Server since SQL Server 2000.

iTVFs remain a very useful tool in our SQL armoury, so let's quickly revisit them and the different ways we can use them in our code.

RE: Looking for single system query to return the rowcount of all tables in a DB

or you can try this. sp_msforeachtable @command1 = 'print ''?''' ,  @command2 = 'select count (*) from ?'  sp_msforeachtable will perform up to three commands on each table in the database. When running, it replaces the ? with the name of the table.