org.apache.drill.exec.planner.index

Class MapRDBFunctionalIndexInfo

java.lang.Object

org.apache.drill.exec.planner.index.MapRDBFunctionalIndexInfo

All Implemented Interfaces:

FunctionalIndexInfo

public class MapRDBFunctionalIndexInfo
extends Object
implements FunctionalIndexInfo

Constructor Summary

Constructors

Constructor and Description
MapRDBFunctionalIndexInfo(IndexDescriptor indexDesc)

Method Summary

Modifier and Type	Method and Description
Set<SchemaPath>	allNewSchemaPaths()
Set<SchemaPath>	allPathsInFunction()
Map<LogicalExpression,LogicalExpression>	getExprMap()
IndexDescriptor	getIndexDesc()
SchemaPath	getNewPath(SchemaPath path) getNewPath: for an original path, return new rename '$N' path, notice there could be multiple renamed paths if the there are multiple functional indexes refer original path.
SchemaPath	getNewPathFromExpr(LogicalExpression expr) return a plain field path if the incoming index expression 'expr' is replaced to be a plain field
Map<LogicalExpression,Set<SchemaPath>>	getPathsInFunctionExpr() Suppose the index key has functions (rather than plain columns): CAST(a as int), CAST(b as varchar(10)), then we want to maintain a mapping of the logical expression of that function to the schema path of the base column involved in the function.
boolean	hasFunctional()
boolean	supportEqualCharConvertToLike() Whether this implementation( may be different per storage) support rewrite rewriting varchar equality expression, e.g.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MapRDBFunctionalIndexInfo

public MapRDBFunctionalIndexInfo(IndexDescriptor indexDesc)

Method Detail

hasFunctional

public boolean hasFunctional()

Specified by:

hasFunctional in interface FunctionalIndexInfo

Returns:

if this index has functional indexed field, return true

getIndexDesc

public IndexDescriptor getIndexDesc()

Specified by:

getIndexDesc in interface FunctionalIndexInfo

Returns:

the IndexDescriptor this IndexInfo built from

getNewPath

public SchemaPath getNewPath(SchemaPath path)

getNewPath: for an original path, return new rename '$N' path, notice there could be multiple renamed paths if the there are multiple functional indexes refer original path.

Specified by:

getNewPath in interface FunctionalIndexInfo

Parameters:

path -

Returns:

getNewPathFromExpr

public SchemaPath getNewPathFromExpr(LogicalExpression expr)

return a plain field path if the incoming index expression 'expr' is replaced to be a plain field

Specified by:

getNewPathFromExpr in interface FunctionalIndexInfo

Parameters:

expr - suppose to be an indexed expression

Returns:

the renamed schemapath in index table for the indexed expression

getPathsInFunctionExpr

public Map<LogicalExpression,Set<SchemaPath>> getPathsInFunctionExpr()

Suppose the index key has functions (rather than plain columns): CAST(a as int), CAST(b as varchar(10)), then we want to maintain a mapping of the logical expression of that function to the schema path of the base column involved in the function. In this example map has 2 entries: CAST(a as int) --> 'a' CAST(b as varchar(10)) --> 'b'

Specified by:

getPathsInFunctionExpr in interface FunctionalIndexInfo

Returns:

the map of indexed expression --> the involved schema paths in a indexed expression

getExprMap

public Map<LogicalExpression,LogicalExpression> getExprMap()

Specified by:

getExprMap in interface FunctionalIndexInfo

Returns:

the map between indexed expression and to-be-converted target expression for scan in index e.g. cast(a.b as int) -> '$0'

allNewSchemaPaths

public Set<SchemaPath> allNewSchemaPaths()

Specified by:

allNewSchemaPaths in interface FunctionalIndexInfo

Returns:

the set of all new field names for indexed functions in index

allPathsInFunction

public Set<SchemaPath> allPathsInFunction()

Specified by:

allPathsInFunction in interface FunctionalIndexInfo

Returns:

the set of all schemaPath exist in functional index fields

supportEqualCharConvertToLike

public boolean supportEqualCharConvertToLike()

Description copied from interface: FunctionalIndexInfo

Whether this implementation( may be different per storage) support rewrite rewriting varchar equality expression, e.g. cast(a.b as varchar(2)) = 'ca' to LIKE expression: cast(a.b as varchar(2) LIKE 'ca%'

Specified by:

supportEqualCharConvertToLike in interface FunctionalIndexInfo