private HQLContextInterface createHQLContext(
Set<CandidateFact> facts,
Map<Dimension, CandidateDim> dimsToQuery,
Map<CandidateFact, Set<Dimension>> factDimMap)
throws LensException {
if (facts == null || facts.size() == 0) {
return new DimOnlyHQLContext(dimsToQuery, this, this);
} else if (facts.size() == 1 && facts.iterator().next().getStorageTables().size() > 1) {
// create single fact with multiple storage context
return new SingleFactMultiStorageHQLContext(facts.iterator().next(), dimsToQuery, this, this);
} else if (facts.size() == 1 && facts.iterator().next().getStorageTables().size() == 1) {
// create single fact context
return new SingleFactSingleStorageHQLContext(
facts.iterator().next(), dimsToQuery, this, this);
} else {
return new MultiFactHQLContext(facts, dimsToQuery, factDimMap, this);
}
}
String getQBFromString(CandidateFact fact, Map<Dimension, CandidateDim> dimsToQuery)
throws LensException {
String fromString;
if (getJoinAST() == null) {
if (cube != null) {
if (dimensions.size() > 0) {
throw new LensException(LensCubeErrorCode.NO_JOIN_CONDITION_AVAILABLE.getLensErrorInfo());
}
fromString = fact.getStorageString(getAliasForTableName(cube.getName()));
} else {
if (dimensions.size() != 1) {
throw new LensException(LensCubeErrorCode.NO_JOIN_CONDITION_AVAILABLE.getLensErrorInfo());
}
Dimension dim = dimensions.iterator().next();
fromString = dimsToQuery.get(dim).getStorageString(getAliasForTableName(dim.getName()));
}
} else {
StringBuilder builder = new StringBuilder();
getQLString(qb.getQbJoinTree(), builder, fact, dimsToQuery);
fromString = builder.toString();
}
return fromString;
}
public String toHQL() throws LensException {
Set<CandidateFact> cfacts = pickCandidateFactToQuery();
Map<Dimension, CandidateDim> dimsToQuery = pickCandidateDimsToQuery(dimensions);
log.info("facts:{}, dimsToQuery: {}", cfacts, dimsToQuery);
if (autoJoinCtx != null) {
// prune join paths for picked fact and dimensions
autoJoinCtx.pruneAllPaths(cube, cfacts, dimsToQuery);
}
Map<CandidateFact, Set<Dimension>> factDimMap = new HashMap<>();
if (cfacts != null) {
if (cfacts.size() > 1) {
// copy ASTs for each fact
for (CandidateFact cfact : cfacts) {
cfact.copyASTs(this);
factDimMap.put(cfact, new HashSet<>(dimsToQuery.keySet()));
}
}
for (CandidateFact fact : cfacts) {
addRangeClauses(fact);
}
}
// pick dimension tables required during expression expansion for the picked fact and dimensions
Set<Dimension> exprDimensions = new HashSet<Dimension>();
if (cfacts != null) {
for (CandidateFact cfact : cfacts) {
Set<Dimension> factExprDimTables =
exprCtx.rewriteExprCtx(cfact, dimsToQuery, cfacts.size() > 1 ? cfact : this);
exprDimensions.addAll(factExprDimTables);
if (cfacts.size() > 1) {
factDimMap.get(cfact).addAll(factExprDimTables);
}
}
if (cfacts.size() > 1) {
havingAST = MultiFactHQLContext.pushDownHaving(havingAST, this, cfacts);
}
} else {
// dim only query
exprDimensions.addAll(exprCtx.rewriteExprCtx(null, dimsToQuery, this));
}
dimsToQuery.putAll(pickCandidateDimsToQuery(exprDimensions));
log.info("facts:{}, dimsToQuery: {}", cfacts, dimsToQuery);
// pick denorm tables for the picked fact and dimensions
Set<Dimension> denormTables = new HashSet<Dimension>();
if (cfacts != null) {
for (CandidateFact cfact : cfacts) {
Set<Dimension> factDenormTables =
deNormCtx.rewriteDenormctx(cfact, dimsToQuery, cfacts.size() > 1);
denormTables.addAll(factDenormTables);
if (cfacts.size() > 1) {
factDimMap.get(cfact).addAll(factDenormTables);
}
}
} else {
denormTables.addAll(deNormCtx.rewriteDenormctx(null, dimsToQuery, false));
}
dimsToQuery.putAll(pickCandidateDimsToQuery(denormTables));
log.info("facts:{}, dimsToQuery: {}", cfacts, dimsToQuery);
// Prune join paths once denorm tables are picked
if (autoJoinCtx != null) {
// prune join paths for picked fact and dimensions
autoJoinCtx.pruneAllPaths(cube, cfacts, dimsToQuery);
}
if (autoJoinCtx != null) {
// add optional dims from Join resolver
Set<Dimension> joiningTables = new HashSet<Dimension>();
if (cfacts != null && cfacts.size() > 1) {
for (CandidateFact cfact : cfacts) {
Set<Dimension> factJoiningTables =
autoJoinCtx.pickOptionalTables(cfact, factDimMap.get(cfact), this);
factDimMap.get(cfact).addAll(factJoiningTables);
joiningTables.addAll(factJoiningTables);
}
} else {
joiningTables.addAll(autoJoinCtx.pickOptionalTables(null, dimsToQuery.keySet(), this));
}
dimsToQuery.putAll(pickCandidateDimsToQuery(joiningTables));
}
log.info("Picked Fact:{} dimsToQuery: {}", cfacts, dimsToQuery);
pickedDimTables = dimsToQuery.values();
pickedFacts = cfacts;
if (cfacts != null) {
if (cfacts.size() > 1) {
// Update ASTs for each fact
for (CandidateFact cfact : cfacts) {
cfact.updateASTs(this);
}
whereAST =
MultiFactHQLContext.convertHavingToWhere(
havingAST, this, cfacts, new DefaultAliasDecider());
}
}
hqlContext = createHQLContext(cfacts, dimsToQuery, factDimMap);
return hqlContext.toHQL();
}