A named collection of schemas. In OpenEdge SQL, a catalog logically corresponds to a database.
Schema
A collection of tables and other database objects.
Table
A collection of data organized into columns and rows.
Catalogs are used as name components to identify columns and tables in a multi-database query. A table name can have up to three components: catalog.schema.table-name. A column name can have up to four components: catalog.schema.table.column-name.
The primary database—already connected when an OpenEdge SQL process attaches to the OpenEdge SQL Server—is already assigned the name of the primary database as its catalog name. Each auxiliary database is assigned a name when the CONNECT AS CATALOG command is executed.
Note: Catalogs cannot be used in Data Definition Language statements such as ALTER and CREATE. Nor can they be used with sequences.