Each column in a table has a particular data type associated
with it. SQL-92 defines a fairly broad set of data types . Different RDBMS packages provide extensions to these
basic types, for multimedia data, Java objects, and so on. Oracle’s
NUMBER data type, for instance,
allows database designers to specify the exact precision of integer
and floating-point data types. The basic SQL-92 types are listed in
Table D-1. The names
in parentheses are SQL-92-specified alternates for the main type
Table D-1. SQL-92 data types
SQL data type
A signed integer value. The number of bits represented is implementation-dependent.
A smaller signed integer value, used when storage or memory is at a premium. Generally 8 bits but implementation-dependent.
A signed fixed-precision decimal.
When creating a
Defined the same way as a
A single-precision floating-point value. Range and accuracy are implementation-dependent.
DOUBLE PRECISION (DOUBLE)
A double-precision floating-point
value. Range and accuracy are implementation-dependent, but
are equal to or better than a
A fixed number (one or more) of
bits. A length specifier (