SQL-92

Last updated
SQL-92
First publishedNovember 1992
Domain SQL

SQL-92 was the third revision of the SQL database query language. Unlike SQL-89, it was a major revision of the standard. Aside from a few minor incompatibilities, the SQL-89 standard is forward-compatible with SQL-92.

Contents

The standard specification itself grew about five times compared to SQL-89. Much of it was due to more precise specifications of existing features; the increase due to new features was only by a factor of 1.52. Many of the new features had already been implemented by vendors before the new standard was adopted. [1] However, most of the new features were added to the "intermediate" and "full" tiers of the specification, meaning that conformance with SQL-92 entry level was scarcely any more demanding than conformance with SQL-89.

Later revisions of the standard include SQL:1999 (SQL3), SQL:2003, SQL:2008, SQL:2011, SQL:2016 and SQL:2023.

New features

Significant new features include: [2]

Extensions

Two significant extensions were published after standard (but before the next major iteration.)

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References

  1. Jim Melton; Alan R. Simon (1993). Understanding The New SQL: A Complete Guide . Morgan Kaufmann. pp.  11–12. ISBN   978-1-55860-245-8.
  2. C. J. Date with Hugh Darwen: A Guide to the SQL standard : a users guide to the standard database language SQL, 4th ed., Addison Wesley, USA 1997, ISBN   978-0-201-96426-4