ANALYZE Statement
Syntax:
ANALYZE TABLE tablename COMPUTE|ESTIMATE|DELETE STATISTICS ptnOption options
ANALYZE INDEX indexname COMPUTE|ESTIMATE|DELETE STATISTICS ptnOption options
ANALYZE CLUSTER clustername COMPUTE|ESTIMATE|DELETE STATISTICS options
ptnOption
PARTITION (partion)
SUBPARTITION (subpartition)
options
VALIDATE STRUCTURE [CASCADE] [INTO tablename]
LIST CHAINED ROWS [INTO tablename]
COMPUTE|ESTIMATE STATISTICS FOR TABLE
COMPUTE|ESTIMATE STATISTICS FOR ALL COLUMNS
COMPUTE|ESTIMATE STATISTICS FOR ALL INDEXED COLUMNS
COMPUTE|ESTIMATE STATISTICS FOR COLUMNS [SIZE int] column [SIZE int]
When Estimating statistics you can optionally
specify
... ESTIMATE STATISTICS SAMPLE n ROWS
... ESTIMATE STATISTICS SAMPLE n PERCENT
Validate structure will perform an integrity check - and will therefore lock the table/index/cluster while it is running.
If the INTO clause is used to store a list of chained rows in a table - the default tablename is CHAINED_ROWS
UTLCHAIN.sql - creates the chained_rows table
The ANALYZE command is available for all versions of Oracle, however to obtain faster and better statistics use the procedures supplied - in 7.3.4 and 8.0 DBMS_UTILITY.ANALYZE_SCHEMA, and in 8i and above - DBMS_STATS.GATHER_SCHEMA_STATS
"50% of the population has a below average understanding of statistics."- Anon
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