/**
* Initialize the order by list. This call may extend the expressions list.
*
* @param session the session
* @param expressions the select list expressions
* @param expressionSQL the select list SQL snippets
* @param orderList the order by list
* @param visible the number of visible columns in the select list
* @param mustBeInResult all order by expressions must be in the select list
* @param filters the table filters
*/
static void initOrder(
Session session,
ArrayList<Expression> expressions,
ArrayList<String> expressionSQL,
ArrayList<SelectOrderBy> orderList,
int visible,
boolean mustBeInResult,
ArrayList<TableFilter> filters) {
Database db = session.getDatabase();
for (SelectOrderBy o : orderList) {
Expression e = o.expression;
if (e == null) {
continue;
}
// special case: SELECT 1 AS A FROM DUAL ORDER BY A
// (oracle supports it, but only in order by, not in group by and
// not in having):
// SELECT 1 AS A FROM DUAL ORDER BY -A
boolean isAlias = false;
int idx = expressions.size();
if (e instanceof ExpressionColumn) {
// order by expression
ExpressionColumn exprCol = (ExpressionColumn) e;
String tableAlias = exprCol.getOriginalTableAliasName();
String col = exprCol.getOriginalColumnName();
for (int j = 0; j < visible; j++) {
boolean found = false;
Expression ec = expressions.get(j);
if (ec instanceof ExpressionColumn) {
// select expression
ExpressionColumn c = (ExpressionColumn) ec;
found = db.equalsIdentifiers(col, c.getColumnName());
if (found && tableAlias != null) {
String ca = c.getOriginalTableAliasName();
if (ca == null) {
found = false;
if (filters != null) {
// select id from test order by test.id
for (int i = 0, size = filters.size(); i < size; i++) {
TableFilter f = filters.get(i);
if (db.equalsIdentifiers(f.getTableAlias(), tableAlias)) {
found = true;
break;
}
}
}
} else {
found = db.equalsIdentifiers(ca, tableAlias);
}
}
} else if (!(ec instanceof Alias)) {
continue;
} else if (tableAlias == null && db.equalsIdentifiers(col, ec.getAlias())) {
found = true;
} else {
Expression ec2 = ec.getNonAliasExpression();
if (ec2 instanceof ExpressionColumn) {
ExpressionColumn c2 = (ExpressionColumn) ec2;
String ta = exprCol.getSQL();
String tb = c2.getSQL();
String s2 = c2.getColumnName();
found = db.equalsIdentifiers(col, s2);
if (!db.equalsIdentifiers(ta, tb)) {
found = false;
}
}
}
if (found) {
idx = j;
isAlias = true;
break;
}
}
} else {
String s = e.getSQL();
if (expressionSQL != null) {
for (int j = 0, size = expressionSQL.size(); j < size; j++) {
String s2 = expressionSQL.get(j);
if (db.equalsIdentifiers(s2, s)) {
idx = j;
isAlias = true;
break;
}
}
}
}
if (!isAlias) {
if (mustBeInResult) {
throw DbException.get(ErrorCode.ORDER_BY_NOT_IN_RESULT, e.getSQL());
}
expressions.add(e);
String sql = e.getSQL();
expressionSQL.add(sql);
}
o.columnIndexExpr = ValueExpression.get(ValueInt.get(idx + 1));
Expression expr = expressions.get(idx).getNonAliasExpression();
o.expression = expr;
}
}
@Override
protected LocalResult queryWithoutCache(int maxRows, ResultTarget target) {
if (maxRows != 0) {
// maxRows is set (maxRows 0 means no limit)
int l;
if (limitExpr == null) {
l = -1;
} else {
Value v = limitExpr.getValue(session);
l = v == ValueNull.INSTANCE ? -1 : v.getInt();
}
if (l < 0) {
// for limitExpr, 0 means no rows, and -1 means no limit
l = maxRows;
} else {
l = Math.min(l, maxRows);
}
limitExpr = ValueExpression.get(ValueInt.get(l));
}
if (session.getDatabase().getSettings().optimizeInsertFromSelect) {
if (unionType == UNION_ALL && target != null) {
if (sort == null && !distinct && maxRows == 0 && offsetExpr == null && limitExpr == null) {
left.query(0, target);
right.query(0, target);
return null;
}
}
}
int columnCount = left.getColumnCount();
LocalResult result = new LocalResult(session, expressionArray, columnCount);
if (sort != null) {
result.setSortOrder(sort);
}
if (distinct) {
left.setDistinct(true);
right.setDistinct(true);
result.setDistinct();
}
if (randomAccessResult) {
result.setRandomAccess();
}
switch (unionType) {
case UNION:
case EXCEPT:
left.setDistinct(true);
right.setDistinct(true);
result.setDistinct();
break;
case UNION_ALL:
break;
case INTERSECT:
left.setDistinct(true);
right.setDistinct(true);
break;
default:
DbException.throwInternalError("type=" + unionType);
}
ResultInterface l = left.query(0);
ResultInterface r = right.query(0);
l.reset();
r.reset();
switch (unionType) {
case UNION_ALL:
case UNION:
{
while (l.next()) {
result.addRow(convert(l.currentRow(), columnCount));
}
while (r.next()) {
result.addRow(convert(r.currentRow(), columnCount));
}
break;
}
case EXCEPT:
{
while (l.next()) {
result.addRow(convert(l.currentRow(), columnCount));
}
while (r.next()) {
result.removeDistinct(convert(r.currentRow(), columnCount));
}
break;
}
case INTERSECT:
{
LocalResult temp = new LocalResult(session, expressionArray, columnCount);
temp.setDistinct();
temp.setRandomAccess();
while (l.next()) {
temp.addRow(convert(l.currentRow(), columnCount));
}
while (r.next()) {
Value[] values = convert(r.currentRow(), columnCount);
if (temp.containsDistinct(values)) {
result.addRow(values);
}
}
break;
}
default:
DbException.throwInternalError("type=" + unionType);
}
if (offsetExpr != null) {
result.setOffset(offsetExpr.getValue(session).getInt());
}
if (limitExpr != null) {
Value v = limitExpr.getValue(session);
if (v != ValueNull.INSTANCE) {
result.setLimit(v.getInt());
}
}
result.done();
if (target != null) {
while (result.next()) {
target.addRow(result.currentRow());
}
result.close();
return null;
}
return result;
}