/**
* 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;
}
}
