The columns Information Schema View

The columns Information Schema view contains one row for each accessible column. It contains the following columns.
Table 1. Description of the columns Information Schema View
Column Data Type Explanation
table_schema VARCHAR(128) Name of owner of table
table_name VARCHAR(128) Name of table or view
column_name VARCHAR(128) Name of the column in the table or view
ordinal_position INTEGER Position of the column within its table

The ordinal_position value is a sequential number that starts at 1 for the first column. This is the HCL Informix® extension to XPG4.
data_type VARCHAR(254) Name of the data type of the column, such as CHARACTER or DECIMAL
char_max_length INTEGER Maximum length (in bytes) for character data types; NULL otherwise
numeric_precision INTEGER Uses one of the following values:
  • Total number of digits for exact numeric data types (DECIMAL, INTEGER, MONEY, SMALLINT)
  • Number of digits of mantissa precision (machine-dependent) for approximate data types (FLOAT, SMALLFLOAT)
  • NULL for all other data types.
numeric_prec_radix INTEGER Uses one of the following values:
  • 2 = Approximate data types (FLOAT and SMALLFLOAT)
  • 10 = Exact numeric data types (DECIMAL, INTEGER, MONEY, and SMALLINT)
  • NULL for all other data types
numeric_scale INTEGER Number of significant digits to the right of the decimal point for DECIMAL and MONEY data types

0 for INTEGER and SMALLINT types NULL for all other data types
datetime_precision INTEGER Number of digits in the fractional part of the seconds for DATE and DATETIME columns; NULL otherwise

This column is the HCL Informix® extension to XPG4.
is_nullable VARCHAR(3) Indicates whether a column allows NULL values; either YES or NO
remarks VARCHAR(254) Reserved for future use