Data Query Language (DQL)
DQL commands are basically SELECT statements. SELECT statements let you query the database to find information in one or more tables, and return the query as a result set. A result set is an array structure; or more precisely, a result set is a two-dimensional array. The internal index for each row of data is the rowid pseudo-column, which maps to the physical address for where the data is written.
NOTE
A SELECT statement with a FOR UPDATE clause is a transaction and DML statement, not a DQL query. This is a fine distinction, but critical should you encounter an ORA-22292 error while working with the DBMS_LOB package ...
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