Neoview SQL Reference Manual (R2.3)

Reporting of Updates...............................................................................................................182
Updating Character Values......................................................................................................182
SET Clause Restrictions and Error Cases.................................................................................183
SET ON ROLLBACK Considerations......................................................................................183
SET ON ROLLBACK Restrictions............................................................................................183
Examples of UPDATE....................................................................................................................183
UPDATE STATISTICS Statement........................................................................................................185
Syntax Description of UPDATE STATISTICS................................................................................185
Considerations for UPDATE STATISTICS.....................................................................................188
Physical Statistics......................................................................................................................188
Using Statistics.........................................................................................................................188
Authorization and Locking......................................................................................................188
Transactions..............................................................................................................................188
Generating and Clearing Statistics for Columns......................................................................188
Column Lists and Access Plans................................................................................................189
Examples of UPDATE STATISTICS...............................................................................................189
3 SQL Utilities................................................................................................................191
Privileges Required to Execute Utilities .............................................................................................191
MAINTAIN Command.......................................................................................................................192
Syntax Description of MAINTAIN................................................................................................192
MAINTAIN MVGROUP................................................................................................................194
Examples of MAINTAIN...............................................................................................................195
POPULATE INDEX Utility.................................................................................................................197
Syntax Description of POPULATE INDEX....................................................................................197
Considerations for POPULATE INDEX........................................................................................197
Examples of POPULATE INDEX...................................................................................................197
PURGEDATA Utility...........................................................................................................................198
Syntax Description of PURGEDATA.............................................................................................198
Considerations for PURGEDATA..................................................................................................198
Examples of PURGEDATA............................................................................................................198
4 SQL Language Elements...........................................................................................199
Character Sets......................................................................................................................................200
Columns..............................................................................................................................................201
Column References........................................................................................................................201
Derived Column Names................................................................................................................201
Column Default Settings................................................................................................................201
Examples of Derived Column Names...........................................................................................201
Constraints..........................................................................................................................................203
Creating, Adding, and Dropping Constraints on SQL Tables.......................................................203
Constraint Names.....................................................................................................................203
Correlation Names..............................................................................................................................204
Explicit Correlation Names...........................................................................................................204
Implicit Correlation Names...........................................................................................................204
Examples of Correlation Names....................................................................................................204
Database Objects.................................................................................................................................205
Ownership.....................................................................................................................................205
Database Object Names......................................................................................................................206
Logical Names for SQL Objects.....................................................................................................206
SQL Object Namespaces................................................................................................................206
Data Types...........................................................................................................................................207
Comparable and Compatible Data Types.....................................................................................209
10 Table of Contents