Size of identifiers

Avoid using long database object names.

The maximum size of a table or column name depends on the database server type. Some database engines allow very large names (256c), while others support only short names (30c max). Therefore, using short names is required for writing portable SQL. Short names also simplify SQL programs.

We recommend that you use simple and short (<30c) database object names, without double quotes and without a schema/owner prefix:
CREATE TABLE customer ( cust_id INTEGER )
SELECT customer.cust_id FROM table

You may need to set the database schema after connection, so that the current database user can see the application tables without specifying the owner/schema prefix each time.

Tip: Even if all database engines do not required unique column names for all tables, we recommend that you define column names with a small table prefix (for example, CUST_ID in CUSTOMER table).