/**
* Adds column to RR, checking for duplicate columns. Needed because CBO cannot handle the Hive
* behavior of blindly overwriting old mapping in RR and still somehow working after that.
*
* @return True if mapping was added without duplicates.
*/
public boolean putWithCheck(
String tabAlias, String colAlias, String internalName, ColumnInfo newCI)
throws SemanticException {
ColumnInfo existing = get(tabAlias, colAlias);
// Hive adds the same mapping twice... I wish we could fix stuff like that.
if (existing == null) {
put(tabAlias, colAlias, newCI);
return true;
} else if (existing.isSameColumnForRR(newCI)) {
return true;
}
LOG.warn(
"Found duplicate column alias in RR: "
+ existing.toMappingString(tabAlias, colAlias)
+ " adding "
+ newCI.toMappingString(tabAlias, colAlias));
if (internalName != null) {
existing = get(tabAlias, internalName);
if (existing == null) {
put(tabAlias, internalName, newCI);
return true;
} else if (existing.isSameColumnForRR(newCI)) {
return true;
}
LOG.warn(
"Failed to use internal name after finding a duplicate: "
+ existing.toMappingString(tabAlias, internalName));
}
return false;
}
