Why is ANSI-89 SQL Still Used Despite the Advantages of ANSI-92?

ANSI-92 SQL: Why the Lag in Adoption?

While the ANSI-92 SQL standard debuted over 30 years ago, many developers still rely on the older ANSI-89 standard. This article examines the reasons for this continued use of ANSI-89 and explores whether ANSI-92 provides any performance gains.

ANSI-89's comma-based join syntax can become unwieldy in complex queries. ANSI-92's "JOIN" keyword, grouping join conditions with tables, offers a cleaner, more readable structure. Similarly, ANSI-92 provides a more straightforward syntax for outer joins, replacing the older ( ) notation with explicit keywords.

Experts attribute the slow adoption of ANSI-92 to a perceived lack of performance improvements. Research by Peter Gulutzan and Trudy Pelzer indicates that most database systems optimize both ANSI-89 and ANSI-92 syntax equally, converting them to an internal format before execution.

Familiarity and established practices also play a role. The habit of copying and pasting code, combined with ingrained pattern recognition, can create resistance to adopting new syntax. Nevertheless, ANSI-92 usage is steadily growing, reflecting its broad support across major SQL database vendors.

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