Function of JoinIndexColumns
Captures the columns that form the join index identified by JINumber during index analysis using INITIATE INDEX ANALYSIS.
JoinIndexColumns Table Definition
The following CREATE TABLE request defines JoinIndexColumns:
CREATE TABLE JoinIndexColumns ( WorkLoadID INTEGER NOT NULL, RecommendationID INTEGER NOT NULL, TableID BYTE(6) NOT NULL, JINumber INTEGER NOT NULL, ColumnName VARCHAR128 CHARACTER SET UNICODE NOT CASESPECIFIC DEFAULT NULL, AliasName VARCHAR128 CHARACTER SET UNICODE NOT CASESPECIFIC DEFAULT NULL, Field1Flag CHARACTER(1) CHARACTER SET LATIN NOT CASESPECIFIC DEFAULT NULL, Field2Flag CHARACTER(1) CHARACTER SET LATIN NOT CASESPECIFIC DEFAULT NULL, RowIDFlag CHARACTER(1) CHARACTER SET LATIN NOT CASESPECIFIC DEFAULT NULL, AggregateFunc BYTEINT DEFAULT NULL, PrimaryIndexPosition BYTEINT DEFAULT NULL, GroupByPosition BYTEINT DEFAULT NULL) PRIMARY INDEX (RecommendationID, TableID, JINumber);
Attribute Definitions for JoinIndexColumns
The following table defines the JoinIndexColumns table attributes:
| Attribute | Description |
|---|---|
| WorkLoadID | Uniquely identifies the workload analyzed to create this join index recommendation. |
| RecommendationID |
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| TableID |
|
| JINumber |
|
| ColumnName | Name of the join index column. |
| AliasName | The correlation name assigned to a column or aggregate function in the join index definition. |
| Field1Flag | Indicates whether the column is part of the column_1 (uncompressed columns) select list in the join index definition.
|
| Field2Flag | Indicates whether the column is part of the column_2 (compressed columns) select list in the join index definition.
|
| RowIDFlag | Indicates whether the value for the column is the reserved word ROWID.
|
| AggregateFunc | Indicates whether an aggregate function is applied to ColumnName and, if so, the type of aggregation performed.
|
| PrimaryIndexPosition | Indicates whether ColumnName is a component of the primary index for the join index.
|
| GroupByPosition | Indicates whether ColumnName is a component of the GROUP BY clause in the join index definition.
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