Should I use != or <> for not equal in T-SQL?

Question

I have seen SQL that uses both != and <> for not equal. What is the preferred syntax and why?

Answer 1

Most databases support != (popular programming languages) and <> (ANSI).

Databases that support both != and <>:

• MySQL 5.1: != and <>
• PostgreSQL 8.3: != and <>
• SQLite: != and <>
• Oracle 10g: != and <>
• Microsoft SQL Server 2000/2005/2008/2012/2016: != and <>
• IBM Informix Dynamic Server 10: != and <>
• InterBase/Firebird: != and <>
• Apache Derby 10.6: != and <>
• Sybase Adaptive Server Enterprise 11.0: != and <>

Databases that support the ANSI standard operator, exclusively:

• IBM DB2 UDB 9.5: <>
• Microsoft Access 2010: <>