SQL Server Backward Compatibility Details

Microsoft understands that introducing a major release of Microsoft® SQL Server™ can be both exciting and challenging, and has worked hard at making the SQL Server version 7.0 upgrade as easy as possible by:

Adding functionality, either new to SQL Server 7.0 or changed from earlier versions, which makes it easier, faster, and more efficient for you to accomplish your tasks related to SQL Server.
Minimizing the time and effort needed to upgrade.

SQL Server 7.0 adds many new features and architectural changes. Most of the changes are internal and will not affect your database scripts or applications. All Transact-SQL statements are compatible; however, administration tools or scripts should be updated to work with SQL Server 7.0.

For more information about upgrading your databases to SQL Server 7.0, see Upgrading from an Earlier Version of SQL Server.

These backward compatibility topics contain a complete and detailed list of changed features and behavior that could possibly affect your administration tool or script and are not controlled by the backward compatibility level.

To indicate their potential effect on administration tools or scripts, feature changes have been grouped into four levels.

Level	Consists of
1	Administrative statements, stored procedures, or SQL Server items that have been removed from, or are no longer supported in, SQL Server 7.0. Administrative tools or scripts using these items must be fixed prior to using SQL Server 7.0.
2	Important changes that produce different behavior from earlier versions of SQL Server. For example, items in this category are those that have changed behavior in data type conversion or usage of selected functions, changed behavior of clauses in selected Transact-SQL statements and stored procedures, changed column names in selected system tables, and changed behavior due to the database compatibility setting.
3	Items supported for backward compatibility only. Any item included in this category is fully supported, but may be removed or unsupported in a future release. SQL Server 7.0 provides features that accomplish these tasks more efficiently and have ongoing support.
4	Minor changes that produce different behavior from earlier versions of SQL Server. For example, items in this category are either ignored or have one or more ignored parameters, changed byte lengths, added parameters or columns, or changed data type columns.