16.20 - CHECKSUM - Teradata Database - Teradata Vantage NewSQL Engine

A table-specific disk I/O integrity checksum level. The checksum setting applies to primary and fallback data rows for the hash index.

If you do not specify a value, the system assumes the system-wide default value for this table type. The result is identical to specifying DEFAULT. If you are changing the checksum for this table to the system-wide default value, then specify DEFAULT.

ON

Calculate checksums using the entire disk block. Sample 100% of the disk blocks to generate a checksum. ON is equivalent to ALL, which is deprecated.

DEFAULT

The default setting is the current DBS Control checksum setting specified for this table type.

OFF

Disables checksum disk I/O integrity checks. OFF is equivalent to NONE, which is deprecated.

Example: Hash Index With Checksum

     CREATE HASH INDEX line_hidx_6, CHECKSUM=ON 
       (l.shipdate) ON lineitem
     BY (l_shipdate)
     ORDER BY VALUES;

     CREATE JOIN INDEX line_jidx_6, CHECKSUM=ON AS
      SELECT (l_orderkey), (l_shipdate, lineitem.ROWID) 
      FROM lineitem
      ORDER BY l_orderkey
     PRIMARY INDEX (l_shipdate);