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3.3. pg_attrdef

This catalog stores column default values. The main information about columns is stored in pg_attribute (see below). Only columns that explicitly specify a default value (when the table is created or the column is added) will have an entry here.

Table 3-3. pg_attrdef Columns

Name Type References Description
adrelid oid pg_class.oid The table this column belongs to
adnum int2   The number of the column; see pg_attribute.pg_attnum
adbin text   An internal representation of the column default value
adsrc text   A human-readable representation of the default value