Sql Server Limitations

The following table specifies the maximum sizes and numbers of various objects defined in SQL Server databases or referenced in Transact-SQL statements.

Sql Server Objects	Limits(32-Bit)	Limits (64-Bit)
Bytes per foreign key	900	900
Bytes per primary key	900	900
Bytes per foreign key	900	900
Bytes per primary key	900	900
Bytes per row	8060	8060
Bytes per varchar(max), varbinary(max), xml, text, or image column	2^31-1	2^31-1
Characters per ntext or nvarchar(max) column	2^30-1	2^30-1
Clustered indexes per table	1	1
Columns in GROUP BY, ORDER BY	Limited only by number of bytes	Limited only by number of bytes
Columns per index key	16	16
Columns per Foreign key	16	16
Columns per Primary key	16	16
Columns per SELECT statement	4,096	4,096
Columns per INSERT statement	4,096	4,096
Database size	524,272 terabytes	524,272 terabytes
Databases per instance of SQL Server	32,767	32,767
Files per database	32,767	32,767
Foreign key table references per table	253	253
Locks per connection	Maximum locks per server	Maximum locks per server
Nested stored procedure levels	32	32
Nested subqueries	32	32
Nested trigger levels	32	32
Parameters per stored procedure	2,100	2,100
Rows per table	Limited by available storage	Limited by available storage
User connections	32,767	32,767
XML indexes	249	249