- MAP
- You can specify an existing contiguous or sparse map for the hash index.
- map_name
- Name of an existing contiguous or sparse map.
- colocation_name
- Name for colocating the hash index on the same AMPs with other tables, join indexes, or hash indexes. For example, you can colocate two tables, then join the tables on the primary index or primary AMP index columns.
- NO
- The hash index does not use fallback protection.You cannot use the NO FALLBACK option and the NO FALLBACK default on platforms optimized for fallback.
- FALLBACK
- The hash index uses fallback protection.
- PROTECTION
Optional keyword.
- CHECKSUM
- A table-specific disk I/O integrity checksum level. The checksum setting applies to primary and fallback data rows for the hash index.
- ON
- Calculate checksums using the entire disk block. Sample 100% of the disk blocks to generate a checksum.
- DEFAULT
- The default setting is the current DBS Control checksum setting specified for this table type.
- OFF
- Disables checksum disk I/O integrity checks.
- BLOCKCOMPRESSION
- Specifies whether the data in the hash index should be block-compressed based on the temperature of the cylinders on which it is stored.
- AUTOTEMP
- The compressed state of the data in the hash index can be changed by Vantage at any time based on its temperature.
- DEFAULT
- The hash index uses the compression option (MANUAL, AUTOTEMP or NEVER) set in the DBS Control parameter DefaultTableMode. For details, see Teradata Vantage™ - Database Utilities, B035-1102. Note that value of DefaultTableMode is not saved in the hash index definition as part of a CREATE HASH INDEX request, so a hash index set to DEFAULT is affected by any future change to the DefaultTableMode parameter.
- MANUAL
- That block level compression is applied based on the default for the hash index at the time the hash index is created. Hash indexes can be compressed or uncompressed at any time after loading by using the Ferret COMPRESS and UNCOMPRESS commands. Data inserted into the existing hash index inherits the current compression status of the hash index at the time the data is inserted.
- NEVER
- The hash index is not compressed even if the DBS Control block compression settings indicate otherwise. Vantage rejects Ferret commands to manually compress the hash index, but Ferret commands to decompress the index are valid.