// We peek at the table expression to compute the set of columns of the join
static SQuery _Join(ReaderBase f)
{
f.GetInt();
var st = f.buf.pos;
var d = SDict <int, (long, string)> .Empty;
var c = SDict <int, Serialisable> .Empty;
var nms = SDict <string, long> .Empty;
var left = f._Get() as SQuery ?? throw new StrongException("Query expected");
var outer = f.GetInt() == 1;
var joinType = (JoinType)f.GetInt();
var right = f._Get() as SQuery ?? throw new StrongException("Query expected");
var ab = left.Display.First();
var uses = SDict <long, long> .Empty;
if (joinType.HasFlag(JoinType.Named))
{
var n = f.GetInt();
for (var i = 0; i < n; i++)
{
uses += (f.GetLong(), f.GetLong());
}
}
var k = 0;
for (var lb = left.cpos.First(); ab != null && lb != null; ab = ab.Next(), lb = lb.Next())
{
var col = lb.Value;
var u = ab.Value.Item2;
d += (k, u);
c += (k, col.Item2);
nms += (u.Item2, u.Item1);
k++;
}
ab = right.Display.First();
for (var rb = right.cpos.First(); ab != null && rb != null; ab = ab.Next(), rb = rb.Next())
{
var u = ab.Value.Item2;
var n = u.Item2;
if (joinType == JoinType.Natural && nms.Contains(n))
{
continue;
}
if (uses.Contains(u.Item1))
{
continue;
}
var col = rb.Value;
d += (k, u);
c += (k, col.Item2);
k++;
}
f.buf.pos = st;
return(new SQuery(Types.STableExp, d, c));
}
internal SDbObject SName(string s)
{
long uid;
if (names.Contains(s))
{
uid = names[s];
}
else
{
uid = --_uid;
names += (s, uid);
uids += (uid, s);
}
return(new SDbObject(Types.SName, uid));
}
static void Show(StrongConnect c, DocArray da)
{
List <Column> cols = new List <Column>(); // of Column
SDict <string, int> names = SDict <string, int> .Empty;
SDict <int, SDict <string, string> > rows = SDict <int, SDict <string, string> > .Empty; // of string[]
for (var b = c.description.First(); b != null; b = b.Next())
{
names = names + (b.Value.Item2, b.Value.Item1);
cols.Add(new Column(b.Value.Item2, b.Value.Item2.Length));
}
for (int i = 0; i < da.items.Count; i++)
{
var dc = da[i];
var row = SDict <string, string> .Empty;
for (var j = 0; j < dc.fields.Count; j++)
{
var f = dc.fields[j];
if (f.Key.StartsWith("_"))
{
continue;
}
if (!names.Contains(f.Key))
{
throw new Exception("Unexpected column " + f.Key);
}
var k = names.Lookup(f.Key);
var s = f.Value.ToString();
if (s.Length > cols[k].width)
{
cols[k].width = s.Length;
}
row = row + (f.Key, s);
}
rows = rows + (rows.Length.Value, row);
}
DrawLine(cols);
ShowHeads(cols);
DrawLine(cols);
for (var j = 0; j < rows.Length.Value; j++)
{
ShowRow(rows.Lookup(j), cols);
}
DrawLine(cols);
}