/**
* Gets the join predicate for a sub-query, or branch.
*
* <p>Sample query (1) below exemplifies query where join is not required. Sample query (2) below
* exemplifies query where join is required.
*
* <p>1. SELECT ro.* FROM RegistryObject ro WHERE (ro.status == "<status>")
*
* <p>2. SELECT ro.* FROM RegistryObject ro, VersionInfo v WHERE ((v.parent = ro.id) AND
* v.versionName = "1.2");
*
* <p>ro = parentAlias v = alias status = filterColumn versionName = filterColumn parent =
* foreignKeyColumn id = parent.primaryKeyColumn
*
* <p>This method provides the (v.parent = ro.id) portion. Filters are added elsewhere
*/
protected String getJoinPredicate() {
String joinPredicate = "";
if ((parentQueryProcessor != null) && (foreignKeyColumn != null)) {
String parentAlias = parentQueryProcessor.getAlias();
String parentPrimaryKeyColumn = parentQueryProcessor.getPrimaryKeyColumn();
String parentJoinPredicate = parentQueryProcessor.getJoinPredicate();
// Use full version of appendPredicate() to avoid recursion
joinPredicate =
appendPredicate(
joinPredicate,
parentJoinPredicate,
alias + "." + foreignKeyColumn + " = " + parentAlias + "." + parentPrimaryKeyColumn);
}
return joinPredicate;
}
/*
* Gets the alias name for the table for this FilterQuery within the SELECT stmt.
* Handles case where same table may be used more than once in a SELECT statment.
* Forward to parentProcessor if any since only top level processor is emitting
* SELECT statement that contains all aliases (no nested SELECTs).
*
*/
protected String getAliasForTable(String tableName) {
String alias = null;
if (parentQueryProcessor != null) {
alias = parentQueryProcessor.getAliasForTable(tableName);
} else {
alias = tableName.toLowerCase();
String originalAlias = alias;
int i = 0;
while (aliases.contains(alias)) {
alias = originalAlias + i;
i++;
}
addTableNameAndAlias(tableName, alias);
}
return alias;
}
