CHECKSUM - Advanced SQL Engine - Teradata Database

SQL Data Definition Language Syntax and Examples

Product
Advanced SQL Engine
Teradata Database
Release Number
17.05
Published
January 2021
Language
English (United States)
Last Update
2021-01-22
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B035-1144
lifecycle
previous
Product Category
Teradata Vantage™

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

integrity_checking_level

ON
Calculate checksums using the entire disk block. Sample 100% of the disk blocks to generate a checksum.
OFF
Disables checksum disk I/O integrity checks.
DEFAULT
The default setting is the current DBS Control checksum setting specified for this table type.

Example: Specifying a Disk I/O Integrity Checksum for a Join Index

The following example defines a join index with a disk I/O integrity checksum specification of ON. If secondary indexes are defined on ord_cust_idx , then the specified checksum value also applies to them.

    CREATE JOIN INDEX ord_cust_idx, CHECKSUM=ON AS
    SELECT c_nationkey, SUM(o_totalprice(FLOAT)) AS price, o_orderdate 
    FROM orders, customer 
    WHERE o_custkey = c_custkey 
    GROUP BY c_nationkey, o_orderdate
    ORDER BY o_orderdate;