public static List<TableSchemaAttributeDetail> resolve(
SyntaxTreeListNode<SyntaxTreeNode> projectionList, TableSchema schema)
throws SQLSemanticException {
SyntaxTreeNode node = projectionList.getNode();
List<TableSchemaAttributeDetail> result = new LinkedList<TableSchemaAttributeDetail>();
if (node.getClass().equals(SyntaxTreeRenameNode.class)) { // Case 0 :: renamed aggregate
SyntaxTreeRenameNode rdnode = (SyntaxTreeRenameNode) node;
if (rdnode.getChild().getClass().equals(SyntaxTreeIdentifierNode.class)) {
SyntaxTreeIdentifierNode inode = (SyntaxTreeIdentifierNode) rdnode.getChild();
if (inode.generatingToken.tokenClass
== SQLToken.SQLTokenClass
.AGGREGATE) { // aggregates are not renamed in the projection, but in the
// aggregation
int index = schema.indexOfAttributeName(rdnode.name, 0);
result.add(schema.getAttributes().get(index));
} else {
throw new SQLSemanticException(
SQLSemanticException.Type.InternalError); // only rename aggregates
}
} else {
throw new SQLSemanticException(SQLSemanticException.Type.InternalError);
}
} else if (node.getClass()
.equals(SyntaxTreeIdentifierNode.class)) { // Case 1 :: identifier or unnamed aggregate
SyntaxTreeIdentifierNode idnode = (SyntaxTreeIdentifierNode) node;
if (idnode.generatingToken.tokenClass
== SQLToken.SQLTokenClass.STAR) { // Case 1a ::add all attributes from the child schema
result = schema.getAttributes();
} else if (idnode.generatingToken.tokenClass
== SQLToken.SQLTokenClass
.QSTARID) { // Case 1b :: add all attributes that have the right qualifier
List<TableSchemaAttributeDetail> allAttributes = schema.getAttributes();
String attributeQualifier = idnode.generatingToken.getQualifierForIdentifier();
if (!schema.getQualifiers().contains(attributeQualifier)) {
throw new SQLSemanticException(
SQLSemanticException.Type.NoSuchTableException, attributeQualifier);
}
for (TableSchemaAttributeDetail attribute : allAttributes) {
if (attribute.qualifier.equals(attributeQualifier)) {
result.add(attribute);
}
}
} else if (idnode.generatingToken.tokenClass
== SQLToken.SQLTokenClass
.QID) { // Case 1c :: add the first attribute that has the right name and right
// qualifier
Pair<String, String> nameParts = idnode.generatingToken.getFragmentsForIdentifier();
int currentIndex = schema.indexOfQualifiedAttributeName(nameParts.first, nameParts.second);
if (currentIndex < 0)
throw new SQLSemanticException(
SQLSemanticException.Type.NoSuchAttributeException, nameParts.second);
result.add(schema.getAttributes().get(currentIndex));
} else if (idnode.generatingToken.tokenClass
== SQLToken.SQLTokenClass
.UID) { // Case 1d :: add the first attribute that has the right name
Pair<String, String> nameParts = idnode.generatingToken.getFragmentsForIdentifier();
int index = schema.indexOfAttributeName(nameParts.second, 0);
if (index < 0)
throw new SQLSemanticException(
SQLSemanticException.Type.NoSuchAttributeException, nameParts.second);
result.add(schema.getAttributes().get(index));
} else {
throw new SQLSemanticException(SQLSemanticException.Type.InternalError);
}
} else {
throw new SQLSemanticException(SQLSemanticException.Type.InternalError);
}
if (projectionList.getNext() != null) { // recursively resolve rest of the list and append
result.addAll(resolve(projectionList.getNext(), schema));
}
return result;
}
