15.10 - INDEX, secondary index definition - Teradata Database

Teradata Database SQL Data Definition Language Syntax and Examples

prodname
Teradata Database
vrm_release
15.10
created_date
December 2015
category
Programming Reference
featnum
B035-1144-151K

A keyword used to define secondary indexes for the table. The INDEX list is an extension to ANSI SQL.

UNIQUE
The named column must be unique.
The primary index and any secondary indexes can be defined to be unique. The only exception is if a queue table has only a QITS column. In this case, the QITS column must also be the primary index, so it cannot be a UPI. This is because timestamp values can repeat and therefore cannot be assumed to be unique (see SQL Data Types and Literals, B035-1143).
index_name
Optional name for the index.
For information about naming database objects, see SQL Fundamentals, B035-1141.
index_column_name
A column in the column set whose values are to be used as the basis for a secondary index.
Columns in the list cannot have a BLOB, CLOB, JSON, XML, Period, or Geospatial data type.
If you specify more than one column name, the index is created on the combined values of each column named. A maximum of 64 columns can be specified for an index, and a combined maximum of 32 secondary, hash, and join indexes can be created for one table (a multicolumn NUSI defined with an ORDER BY clause counts as two indexes in this calculation). This includes the system-defined secondary indexes used to implement PRIMARY KEY and UNIQUE constraints for nontemporal tables and the single-table join indexes used to implement PRIMARY KEY and UNIQUE constraints for temporal tables.