public Set<Dimension> rewriteDenormctx(
CandidateFact cfact, Map<Dimension, CandidateDim> dimsToQuery, boolean replaceFact)
throws LensException {
Set<Dimension> refTbls = new HashSet<>();
if (!tableToRefCols.isEmpty()) {
// pick referenced columns for fact
if (cfact != null) {
pickColumnsForTable(cfact.getName());
}
// pick referenced columns for dimensions
if (dimsToQuery != null && !dimsToQuery.isEmpty()) {
for (CandidateDim cdim : dimsToQuery.values()) {
pickColumnsForTable(cdim.getName());
}
}
// Replace picked reference in all the base trees
replaceReferencedColumns(cfact, replaceFact);
// Add the picked references to dimsToQuery
for (PickedReference picked : pickedRefs) {
if (isPickedFor(picked, cfact, dimsToQuery)) {
refTbls.add(
(Dimension) cubeql.getCubeTableForAlias(picked.getChainRef().getChainName()));
cubeql.addColumnsQueried(
picked.getChainRef().getChainName(), picked.getChainRef().getRefColumn());
}
}
}
return refTbls;
}
// checks if the reference if picked for facts and dimsToQuery passed
private boolean isPickedFor(
PickedReference picked, CandidateFact cfact, Map<Dimension, CandidateDim> dimsToQuery) {
if (cfact != null && picked.pickedFor.equalsIgnoreCase(cfact.getName())) {
return true;
}
if (dimsToQuery != null) {
for (CandidateDim cdim : dimsToQuery.values()) {
if (picked.pickedFor.equalsIgnoreCase(cdim.getName())) {
return true;
}
}
}
return false;
}
/**
* Find all de-normalized columns, if these columns are not directly available in candidate
* tables, query will be replaced with the corresponding table reference
*/
@Override
public void rewriteContext(CubeQueryContext cubeql) throws LensException {
DenormalizationContext denormCtx = cubeql.getDeNormCtx();
if (denormCtx == null) {
// Adds all the reference dimensions as eligible for denorm fields
denormCtx = new DenormalizationContext(cubeql);
cubeql.setDeNormCtx(denormCtx);
// add ref columns in cube
addRefColsQueried(cubeql, cubeql, denormCtx);
// add ref columns from expressions
for (Set<ExpressionContext> ecSet : cubeql.getExprCtx().getAllExprsQueried().values()) {
for (ExpressionContext ec : ecSet) {
for (ExprSpecContext esc : ec.getAllExprs()) {
addRefColsQueried(cubeql, esc, denormCtx);
}
}
}
} else if (!denormCtx.tableToRefCols.isEmpty()) {
// In the second iteration of denorm resolver
// candidate tables which require denorm fields and the refernces are no
// more valid will be pruned
if (cubeql.getCube() != null && !cubeql.getCandidateFacts().isEmpty()) {
for (Iterator<CandidateFact> i = cubeql.getCandidateFacts().iterator(); i.hasNext(); ) {
CandidateFact cfact = i.next();
if (denormCtx.tableToRefCols.containsKey(cfact.getName())) {
for (ReferencedQueriedColumn refcol : denormCtx.tableToRefCols.get(cfact.getName())) {
if (denormCtx.getReferencedCols().get(refcol.col.getName()).isEmpty()) {
log.info(
"Not considering fact table:{} as column {} is not available",
cfact,
refcol.col);
cubeql.addFactPruningMsgs(
cfact.fact, CandidateTablePruneCause.columnNotFound(refcol.col.getName()));
i.remove();
}
}
}
}
if (cubeql.getCandidateFacts().size() == 0) {
throw new LensException(
LensCubeErrorCode.NO_FACT_HAS_COLUMN.getLensErrorInfo(),
cubeql.getColumnsQueried(cubeql.getCube().getName()).toString());
}
cubeql.pruneCandidateFactSet(CandidateTablePruneCode.COLUMN_NOT_FOUND);
}
if (cubeql.getDimensions() != null && !cubeql.getDimensions().isEmpty()) {
for (Dimension dim : cubeql.getDimensions()) {
for (Iterator<CandidateDim> i = cubeql.getCandidateDimTables().get(dim).iterator();
i.hasNext(); ) {
CandidateDim cdim = i.next();
if (denormCtx.tableToRefCols.containsKey(cdim.getName())) {
for (ReferencedQueriedColumn refcol : denormCtx.tableToRefCols.get(cdim.getName())) {
if (denormCtx.getReferencedCols().get(refcol.col.getName()).isEmpty()) {
log.info(
"Not considering dim table:{} as column {} is not available",
cdim,
refcol.col);
cubeql.addDimPruningMsgs(
dim,
cdim.dimtable,
CandidateTablePruneCause.columnNotFound(refcol.col.getName()));
i.remove();
}
}
}
}
if (cubeql.getCandidateDimTables().get(dim).size() == 0) {
throw new LensException(
LensCubeErrorCode.NO_DIM_HAS_COLUMN.getLensErrorInfo(),
dim.toString(),
cubeql.getColumnsQueried(dim.getName()).toString());
}
}
}
}
}