Property definitions

The Data Catalog object meta data include attributes to define the property data type, size, and formats. These properties are used to define Compass column definitions.

Property definitions in Compass closely align Data Catalog property definitions with ANSI SQL92 column standards. Compass queries that are executed with the Compass JDBC driver closely align property definitions with Java JDBC version 8 standards. For dates and timestamps, column definitions reflect ISO 8601 RFC 3339 formats, which is the Compass standard format for all dates and timestamps.

The Time format is not supported in Compass explicitly.

Column properties affect these areas:

  • Queries to information_schema directly show attributes, such as column data types, size, and precision.
  • Query result set meta data includes the column definitions.
  • Applications that use the Compass JDBC driver use the column definitions for object tree displays.

ORDINAL_POSITION

The ordinal position is the order of the column within the table. The ordinal position is set by the xposition attribute. For properties without an x-position property, the ordinal position is based on property names in ascending order.

IS_NULLABLE

The IS_NULLABLE is always set to true. Compass does not validate or require values for columns that are defined in the object schema as required or “not nullable”.