Defining Teradata Hash Indexes

The following properties are applicable to a Teradata Hash Index object.

Tab

Property

Description

Additional Information

 

Table

Specifies the table for which you want to create a Hash index

 
  Name Specifies the name of the hash index  
  Database Specifies the database or user  
  Generate Specifies whether a DDL statement is generated for the object during forward engineering  
General Column Specifies the columns for the table that have the index and are key group members  
Options

 

 

 Fallback Protection Specifies the type of fallback protection for the database

Fallback: Indicates that a secondary copy of the table is created and stored for protection

No Fallback: Indicates that no fallback protection is configured
Checksum Specifies the integrity checking level for disk I/O

Default: Indicates that the system-wide default DBS Control checksum setting is applied to the table

On: Indicates that the entire disk block is sampled to calculate a checksum

Off: Indicates that checksum disk I/O integrity checks is disabled

Block Compression

Specifies the block-level compression technique to be used

AutoTemp: Indicates that the file system determines the block-level compression setting for the join index based on its Teradata Virtual Storage temperature

Default: Indicates that the join index uses the compression option setting (MANUAL, AUTOTEMP, or NEVER) of the DBS Control parameter DefaultTableMode.

Manual: Indicates that block-level compression is applied based on the default for the join index at the time the join index is created.

Never: Indicates that the join index is not compressed even if the DBS Control block compression settings indicate otherwise

Order By

Specifies how the rows are ordered

Hash: Indicates that hash-ordering is applied for rows

Value: Indicates that value-ordering is applied for rows

Ordering

 

Hash by Columns

Displays the valid columns that you can select to participate in the hash

 

Order by Columns

Displays the valid columns that you can select to participate in the ordering