The SQL procedure offers
a variety of options that control processing. Some options control
execution. For example, you can limit the number of rows read or written
during a query. Other options control output. For example, you can
control the appearance of long character columns, double-space output,
or (as shown below) number your rows. Options are also available for
testing and evaluating performance.
Metadata is a description or definition
of data or information. SAS session metadata is stored in Dictionary
tables, which are special, read-only SAS tables that contain information
about SAS libraries, SAS data sets, SAS macros, and external files
that are available in the current SAS session. Dictionary tables also
contain the settings for SAS system options and SAS titles and footnotes
that are currently in effect. You can use the SQL procedure to access
the metadata stored in Dictionary tables. For example, you can query
a Dictionary table to find out which tables in a SAS library contain
a specified column.