GemFire 6.6.3

com.gemstone.gemfire.cache.query
Interface Index


public interface Index

An index that is built over the data stored in a GemFire Region.

For a description of the types of indexes that GemFire currently supports, see IndexType.

An index is specified using a name, indexedExpression, fromClause, and optionally a projectionAttributes.

The name uniquely identifies the index to for the statistics services in GemFire.

The indexedExpression is the lookup value for the index. The way that an indexedExpression is specified and used varies depending on the type of index. For more information, see IndexType.

The fromClause specifies the collection(s) of objects that the index ranges over, and must contain one and only one region path.

The optional projectAttributes specifies a tranformation that is done on the values and is used for pre-computing a corresponding projection as defined in a query.

Since:
4.0
See Also:
QueryService.createIndex(String, IndexType, String, String), IndexType

Method Summary
 String getCanonicalizedFromClause()
          Get the canonicalized fromClause for this index.
 String getCanonicalizedIndexedExpression()
          Get the canonicalized indexedExpression for this index.
 String getCanonicalizedProjectionAttributes()
          Get the canonicalized projectionAttributes for this expression.
 String getFromClause()
          Get the original fromClause for this index.
 String getIndexedExpression()
          Get the original indexedExpression for this index.
 String getName()
          Returns the unique name of this index
 String getProjectionAttributes()
          Get the original projectionAttributes for this expression.
 Region<?,?> getRegion()
          The Region this index is on
 IndexStatistics getStatistics()
          Get statistics information for this index.
 IndexType getType()
          Get the index type
 

Method Detail

getName

String getName()
Returns the unique name of this index


getType

IndexType getType()
Get the index type

Returns:
the type of index

getRegion

Region<?,?> getRegion()
The Region this index is on

Returns:
the Region for this index

getStatistics

IndexStatistics getStatistics()
Get statistics information for this index.


getFromClause

String getFromClause()
Get the original fromClause for this index.


getCanonicalizedFromClause

String getCanonicalizedFromClause()
Get the canonicalized fromClause for this index.


getIndexedExpression

String getIndexedExpression()
Get the original indexedExpression for this index.


getCanonicalizedIndexedExpression

String getCanonicalizedIndexedExpression()
Get the canonicalized indexedExpression for this index.


getProjectionAttributes

String getProjectionAttributes()
Get the original projectionAttributes for this expression.

Returns:
the projectionAttributes, or "*" if there were none specified at index creation.

getCanonicalizedProjectionAttributes

String getCanonicalizedProjectionAttributes()
Get the canonicalized projectionAttributes for this expression.

Returns:
the projectionAttributes, or "*" if there were none specified at index creation.

GemFire 6.6.3

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