Describes all indexes on the tables specified by the query.
The following CREATE TABLE request defines IndexTable.
CREATE TABLE IndexTable (
IndexNum INTEGER NOT NULL,
RelationKey INTEGER NOT NULL,
OrderBy CHARACTER(1) CHARACTER SET LATIN NOT CASESPECIFIC
NOT NULL,
AccessInfo CHARACTER(1) CHARACTER SET LATIN NOT CASESPECIFIC
NOT NULL,
Field1Only CHARACTER(1) CHARACTER SET LATIN NOT CASESPECIFIC
NOT NULL,
RangeConstraint CHARACTER(1) CHARACTER SET LATIN NOT CASESPECIFIC
NOT NULL,
IndexFlag CHARACTER(1) CHARACTER SET LATIN NOT CASESPECIFIC,
IndexName VARCHAR128 CHARACTER SET UNICODE NOT CASESPECIFIC,
IndexType CHARACTER(1) CHARACTER SET LATIN NOT CASESPECIFIC,
UniqueFlag CHARACTER(1) CHARACTER SET LATIN NOT CASESPECIFIC,
IndexKind CHARACTER(1) CHARACTER SET LATIN NOT CASESPECIFIC,
NumNulls FLOAT,
NumIntervals INTEGER,
MinValue VARCHAR(512) CHARACTER SET UNICODE
NOT CASESPECIFIC,
ModeValue VARCHAR(512) CHARACTER SET UNICODE
NOT CASESPECIFIC,
ModeFreq FLOAT,
TotalValues FLOAT,
TotalRows FLOAT)
PRIMARY INDEX (RelationKey)
UNIQUE INDEX USK_IdxNum_RelationKey ( IndexNum, RelationKey );
The following table defines the IndexTable table attributes.
Attribute |
Description |
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IndexNum |
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RelationKey |
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OrderBy |
Defines whether the index has an associated ORDER BY clause. |
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AccessInfo |
Specifies if the index is a covering index, bit map, or neither. |
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Field1Only |
Defines whether the index is a join index and Field1 is the only part needed. This means that the join index is not compressed. |
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RangeConstraint |
Flag for value-ordered indexes that have a range constraint used by the query plan. The flag is set to F whether the index is used in the plan or not. |
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IndexFlag |
Flag indicating whether the index was used in the query plan. IndexFlag is also set to T if a subset of the row partitions of a row‑partitioned primary index is accessed because of row partition elimination. |
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IndexName |
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IndexType |
A code indicating the type of the index. |
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UniqueFlag |
Code indicating whether the index is unique or nonunique. |
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IndexKind |
Code indicating whether the index is permanent or simulated. Indexes are simulated using the index validation function of the Teradata Index Wizard (see “Index and Partitioning Expression Validation” on page 845). |
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NumNulls |
The number of nulls in the index. |
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NumIntervals |
The number of intervals in the index statistics. |
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MinValue |
The minimum value of the index. This is obtained from statistical histogram interval 0 for the index. |
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ModeValue |
The value of the index that occurs the most in the table. This is obtained from statistical histogram interval 0 for the index. |
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ModeFreq |
The number of times the modal value occurs in the index. |
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TotalValues |
The total number of values in the index other than the modal value. |
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TotalRows |
The cardinality of the table. |