private TableFilter tFilter; // null if not yet resolved
#endregion Fields
#region Constructors
/**
* Constructor declaration
*
*
* @param f
*/
/* Expression(Function f)
{
iType = FUNCTION;
fFunction = f;
}
*/
/**
* Constructor declaration
*
*
* @param e
*/
public Expression(Expression e)
{
iType = e.iType;
iDataType = e.iDataType;
eArg = e.eArg;
eArg2 = e.eArg2;
cLikeEscape = e.cLikeEscape;
sSelect = e.sSelect;
// fFunction = e.fFunction;
}
/**
* Constructor declaration
*
*
* @param s
*/
public Expression(Select s)
{
iType = QUERY;
sSelect = s;
}
/**
* Method declaration
*
*
* @return
*
* @throws Exception
*/
private Select parseSelect()
{
Select select = new Select();
// [email protected] begin changes from 1.50
select.limitStart = 0;
select.limitCount = cChannel.getMaxRows();
// [email protected] end changes from 1.50
string token = tTokenizer.getstring();
if (token.Equals("DISTINCT"))
{
select.bDistinct = true;
// [email protected] begin changes from 1.50
}
else if( token.Equals("LIMIT"))
{
string limStart = tTokenizer.getstring();
string limEnd = tTokenizer.getstring();
//System.out.println( "LIMIT used from "+limStart+","+limEnd);
select.limitStart = limStart.ToInt32();
select.limitCount = limEnd.ToInt32();
// [email protected] end changes from 1.50
}
else
{
tTokenizer.back();
}
// parse column list
ArrayList vcolumn = new ArrayList();
do
{
Expression e = parseExpression();
token = tTokenizer.getstring();
if (token.Equals("AS"))
{
e.setAlias(tTokenizer.getName());
token = tTokenizer.getstring();
}
else if (tTokenizer.wasName())
{
e.setAlias(token);
token = tTokenizer.getstring();
}
vcolumn.Add(e);
} while (token.Equals(","));
if (token.Equals("INTO"))
{
select.sIntoTable = tTokenizer.getstring();
token = tTokenizer.getstring();
}
if (!token.Equals("FROM"))
{
throw Trace.error(Trace.UNEXPECTED_TOKEN, token);
}
Expression condition = null;
// parse table list
ArrayList vfilter = new ArrayList();
vfilter.Add(parseTableFilter(false));
while (true)
{
token = tTokenizer.getstring();
if (token.Equals("LEFT"))
{
token = tTokenizer.getstring();
if (token.Equals("OUTER"))
{
token = tTokenizer.getstring();
}
Trace.check(token.Equals("JOIN"), Trace.UNEXPECTED_TOKEN,
token);
vfilter.Add(parseTableFilter(true));
tTokenizer.getThis("ON");
condition = addCondition(condition, parseExpression());
}
else if (token.Equals("INNER"))
{
tTokenizer.getThis("JOIN");
vfilter.Add(parseTableFilter(false));
tTokenizer.getThis("ON");
condition = addCondition(condition, parseExpression());
}
else if (token.Equals(","))
{
vfilter.Add(parseTableFilter(false));
}
else
{
break;
}
}
tTokenizer.back();
int len = vfilter.Count;
TableFilter[] filter = new TableFilter[len];
vfilter.CopyTo(filter);
select.tFilter = filter;
// expand [table.]* columns
len = vcolumn.Count;
for (int i = 0; i < len; i++)
{
Expression e = (Expression) (vcolumn[i]);
if (e.getType() == Expression.ASTERIX)
{
int current = i;
Table table = null;
string n = e.getTableName();
for (int t = 0; t < filter.Length; t++)
{
TableFilter f = filter[t];
e.resolve(f);
if (n != null &&!n.Equals(f.getName()))
{
continue;
}
table = f.getTable();
int col = table.getColumnCount();
for (int c = 0; c < col; c++)
{
Expression ins =
new Expression(f.getName(),
table.getColumnName(c));
vcolumn.Insert(current++,ins);
// now there is one element more to parse
len++;
}
}
Trace.check(table != null, Trace.TABLE_NOT_FOUND, n);
// minus the asterix element
len--;
vcolumn.RemoveAt(current);
}
else if (e.getType()==Expression.COLUMN)
{
if (e.getTableName() == null)
{
for (int filterIndex=0; filterIndex < filter.Length; filterIndex++)
{
e.resolve(filter[filterIndex]);
}
}
}
}
select.iResultLen = len;
// where
token = tTokenizer.getstring();
if (token.Equals("WHERE"))
{
condition = addCondition(condition, parseExpression());
token = tTokenizer.getstring();
}
select.eCondition = condition;
if (token.Equals("GROUP"))
{
tTokenizer.getThis("BY");
len = 0;
do
{
vcolumn.Add(parseExpression());
token = tTokenizer.getstring();
len++;
} while (token.Equals(","));
select.iGroupLen = len;
}
if (token.Equals("ORDER"))
{
tTokenizer.getThis("BY");
len = 0;
do
{
Expression e = parseExpression();
if (e.getType() == Expression.VALUE)
{
// order by 1,2,3
if (e.getDataType() == Column.INTEGER)
{
int i = ((int) e.getValue()).ToInt32();
e = (Expression) vcolumn[i - 1];
}
}
else if (e.getType() == Expression.COLUMN
&& e.getTableName() == null)
{
// this could be an alias column
string s = e.getColumnName();
for (int i = 0; i < vcolumn.Count; i++)
{
Expression ec = (Expression) vcolumn[i];
if (s.Equals(ec.getAlias()))
{
e = ec;
break;
}
}
}
token = tTokenizer.getstring();
if (token.Equals("DESC"))
{
e.setDescending();
token = tTokenizer.getstring();
}
else if (token.Equals("ASC"))
{
token = tTokenizer.getstring();
}
vcolumn.Add(e);
len++;
} while (token.Equals(","));
select.iOrderLen = len;
}
len = vcolumn.Count;
select.eColumn = new Expression[len];
vcolumn.CopyTo(select.eColumn);
if (token.Equals("UNION"))
{
token = tTokenizer.getstring();
if (token.Equals("ALL"))
{
select.iUnionType = Select.UNIONALL;
}
else
{
select.iUnionType = Select.UNION;
tTokenizer.back();
}
tTokenizer.getThis("SELECT");
select.sUnion = parseSelect();
}
else if (token.Equals("INTERSECT"))
{
tTokenizer.getThis("SELECT");
select.iUnionType = Select.INTERSECT;
select.sUnion = parseSelect();
}
else if (token.Equals("EXCEPT") || token.Equals("MINUS"))
{
tTokenizer.getThis("SELECT");
select.iUnionType = Select.EXCEPT;
select.sUnion = parseSelect();
}
else
{
tTokenizer.back();
}
return select;
}