Package net.sf.saffron.oj.xlat

Implements translation from standard SQL and OpenJava SQL queries to abstract SaffronRels.

See:
Description

Class Summary

AggInternalTranslator	Converts expressions to consist only of constants, references to group by expressions (variables called "$group0", etc.), and calls to aggregate functions (variables called "$agg0", etc.).
AggInternalTranslator.RexAggVariable	Reference to an aggregation expression of the current aggregator.
AggInternalTranslator.RexGroupVariable	Reference to a key of the current aggregator.
AggUnpickler	Converts references to agg items and aggregates (created by AggInternalTranslator) into more conventional field accesses.
DeferredLookup	Contains the information necessary to repeat a call to QueryInfo.lookup(int,SaffronRel[],boolean,String).
ExtenderAggregation	ExtenderAggregation is an aggregation which works by instantiating a user-defined aggregation (AggregationExtender), as opposed to generating custom code.
InternalTranslator	Converts an Openjava expression into a row-expression.
InternalTranslator.RexQuery	Temporary holder for a scalar query which has not been translated yet.
OJQueryExpander	OJQueryExpander passes over a parse tree, and converts relational expressions into regular Java constructs.
OJSchemaExpander	Replaces references to the virtual members of SaffronSchema expressions.
OpenjavaToSqlConverter	Deprecated. This class is not used.
QueryInfo	A QueryInfo holds all the information about a QueryExpression while it is being translated into a collection of SaffronRels.
QueryInfo.CorrelLookupResult
QueryInfo.LocalLookupResult
QueryInfo.LookupResult
RexToOjTranslator	Converts a row expression to a Java expression.
SqlToOpenjavaConverter	A SqlToOpenjavaConverter converts a tree of SqlNode objects a ParseTree tree.
SqlToOpenjavaConverter.ConverterTest	Unit test for SqlToOpenjavaConverter.
SqlToOpenjavaConverter.SchemaCatalogReader	A SchemaCatalogReader looks up catalog information from a saffron schema object.
SqlToOpenjavaConverter.TestContext
SubqueryFinder
SubqueryFinder.RexExpression	A Row-expression wrapped to look like a Openjava expression.

Exception Summary

NotAGroupException

NotAGroupException is thrown by AggInternalTranslator if it encounters a reference to a variable from the query's from clause.

Package net.sf.saffron.oj.xlat Description

Implements translation from standard SQL and OpenJava SQL queries to abstract SaffronRels.

Revision	$Id: //open/saffron/src/net/sf/saffron/oj/xlat/package.html#2 $
Copyright	(C) Copyright 2003-2003 Disruptive Technologies, Inc.
Author	Julian Hyde