Database entities

The database entity concept across different database engines.

Most database servers can handle multiple database entities (you can create multiple 'databases'), but this is not possible with all engines:

Table 1. Multiple database entities by Database server type
Database Server Type	Multiple Database Entities
Genero db	No
IBM^® DB2^® UDB	Yes
IBM Informix^®	Yes
Microsoft™ SQL Server	Yes
MySQL	Yes
Oracle Database Server	No
PostgreSQL	Yes
Sybase ASE	Yes
SQLite	Yes

When using a database server that does not support multiple database entities, you can emulate different databases with schema entities, but this requires you to check for the database user definition. Each database user must have privileges to access any schema, and to see any table of any schema without needing to set a schema prefix before table names in SQL statements.

Some database drivers allow to select a specific schema at connection with the following FGLPROFILE entry:

dbi.database.dbname.dbtype.schema = "schema-name"

Some databases also allow you to define a default schema for each database user. When the user connects to the database, the default schema is automatically selected.