execplan::ReturnedColumn* buildPseudoColumn(Item* item,
gp_walk_info& gwi,
bool& nonSupport,
uint32_t pseudoType)
{
Item_func* ifp = (Item_func*)item;
// idblocalpm is replaced by constant
if (pseudoType == PSEUDO_LOCALPM)
{
int64_t localPm = idblocalpm();
ConstantColumn* cc;
if (localPm)
cc = new ConstantColumn(localPm);
else
cc = new ConstantColumn("", ConstantColumn::NULLDATA);
cc->alias(ifp->name? ifp->name : "");
return cc;
}
// convert udf item to pseudocolumn item.
// adjust result type
// put arg col to column map
string funcName = ifp->func_name();
if (ifp->arg_count != 1 ||
!(ifp->arguments()) ||
!(ifp->arguments()[0]) ||
ifp->arguments()[0]->type() != Item::FIELD_ITEM)
return nullOnError(gwi, funcName);
Item_field* field = (Item_field*)(ifp->arguments()[0]);
// @todo rule out derive table
if (!field->field || !field->db_name || strlen(field->db_name) == 0)
return nullOnError(gwi, funcName);
SimpleColumn *sc = buildSimpleColumn(field, gwi);
if (!sc)
return nullOnError(gwi, funcName);
if ((pseudoType == PSEUDO_EXTENTMIN || pseudoType == PSEUDO_EXTENTMAX) &&
(sc->colType().colDataType == CalpontSystemCatalog::VARBINARY ||
(sc->colType().colDataType == CalpontSystemCatalog::VARCHAR && sc->colType().colWidth > 7) ||
(sc->colType().colDataType == CalpontSystemCatalog::CHAR && sc->colType().colWidth > 8)))
return nullOnError(gwi, funcName);
// put arg col to column map
if (gwi.clauseType == SELECT || gwi.clauseType == GROUP_BY) // select clause
{
SRCP srcp(sc);
gwi.columnMap.insert(CalpontSelectExecutionPlan::ColumnMap::value_type(sc->columnName(), srcp));
gwi.tableMap[make_aliastable(sc->schemaName(), sc->tableName(), sc->tableAlias(), sc->isInfiniDB())] =
make_pair(1, field->cached_table);
}
else if (!gwi.rcWorkStack.empty())
{
gwi.rcWorkStack.pop();
}
if (pseudoType == PSEUDO_PARTITION)
{
// parms: psueducolumn dbroot, segmentdir, segment
SPTP sptp;
FunctionColumn *fc = new FunctionColumn(funcName);
funcexp::FunctionParm parms;
PseudoColumn *dbroot = new PseudoColumn(*sc, PSEUDO_DBROOT);
sptp.reset(new ParseTree(dbroot));
parms.push_back(sptp);
PseudoColumn *pp = new PseudoColumn(*sc, PSEUDO_SEGMENTDIR);
sptp.reset(new ParseTree(pp));
parms.push_back(sptp);
PseudoColumn* seg = new PseudoColumn(*sc, PSEUDO_SEGMENT);
sptp.reset(new ParseTree(seg));
parms.push_back(sptp);
fc->functionParms(parms);
fc->expressionId(gwi.expressionId++);
// string result type
CalpontSystemCatalog::ColType ct;
ct.colDataType = CalpontSystemCatalog::VARCHAR;
ct.colWidth = 256;
fc->resultType(ct);
// operation type integer
funcexp::Func_idbpartition* idbpartition = new funcexp::Func_idbpartition();
fc->operationType(idbpartition->operationType(parms, fc->resultType()));
fc->alias(ifp->name? ifp->name : "");
return fc;
}
PseudoColumn *pc = new PseudoColumn(*sc, pseudoType);
// @bug5892. set alias for derived table column matching.
pc->alias(ifp->name? ifp->name : "");
return pc;
}
