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Data types concepts ; sql

snippet from reference

4  Concepts

4.1  Data types

A data type is a set of representable values.
The logical representation of a value is a <literal>.
The physical representation of a value is implementation-dependent.
A value is primitive in that it has no logical subdivision
within this International Standard.
A value is a null value or a non-null value.

reference

Carnegie Mellon University, Computer Club, sql, sql1992.txt

at 4.1 Data types

note

  • SQL-92 is obsoleted
  • check yourself latest SQL-2011
  • latest is in ISO/IEC 9075 and non-free