internal override SqlExpression VisitMultiset(SqlSubSelect sms)
{
// allow one big-join per query?
if((this.options & SqlMultiplexerOptionType.EnableBigJoin) != 0 &&
!this.hasBigJoin && this.canJoin && this.isTopLevel && this.outerSelect != null
&& !MultisetChecker.HasMultiset(sms.Select.Selection)
&& BigJoinChecker.CanBigJoin(sms.Select))
{
sms.Select = this.VisitSelect(sms.Select);
SqlAlias alias = new SqlAlias(sms.Select);
SqlJoin join = new SqlJoin(SqlJoinType.OuterApply, this.outerSelect.From, alias, null, sms.SourceExpression);
this.outerSelect.From = @join;
this.outerSelect.OrderingType = SqlOrderingType.Always;
// make joined expression
SqlExpression expr = (SqlExpression)SqlDuplicator.Copy(sms.Select.Selection);
// make count expression
SqlSelect copySelect = (SqlSelect)SqlDuplicator.Copy(sms.Select);
SqlAlias copyAlias = new SqlAlias(copySelect);
SqlSelect countSelect = new SqlSelect(sql.Unary(SqlNodeType.Count, null, sms.SourceExpression), copyAlias, sms.SourceExpression);
countSelect.OrderingType = SqlOrderingType.Never;
SqlExpression count = sql.SubSelect(SqlNodeType.ScalarSubSelect, countSelect);
// make joined collection
SqlJoinedCollection jc = new SqlJoinedCollection(sms.ClrType, sms.SqlType, expr, count, sms.SourceExpression);
this.hasBigJoin = true;
return jc;
}
return QueryExtractor.Extract(sms, this.parentParameters);
}
internal override SqlExpression VisitJoinedCollection(SqlJoinedCollection jc)
{
this.hasSideEffect = true;
return jc;
}
internal virtual SqlExpression VisitJoinedCollection(SqlJoinedCollection jc) {
jc.Expression = this.VisitExpression(jc.Expression);
jc.Count = this.VisitExpression(jc.Count);
return jc;
}
private Type GenerateJoinedCollection(SqlJoinedCollection jc)
{
LocalBuilder locCount = gen.DeclareLocal(typeof(int));
LocalBuilder locHasRows = gen.DeclareLocal(typeof(bool));
Type joinElementType = jc.Expression.ClrType;
Type listType = typeof(List<>).MakeGenericType(joinElementType);
LocalBuilder locList = gen.DeclareLocal(listType);
// count = xxx
this.GenerateExpressionForType(jc.Count, typeof(int));
gen.Emit(OpCodes.Stloc, locCount);
// list = new List<T>(count)
gen.Emit(OpCodes.Ldloc, locCount);
ConstructorInfo ci = listType.GetConstructor(new Type[] { typeof(int) });
Diagnostics.Debug.Assert(ci != null);
gen.Emit(OpCodes.Newobj, ci);
gen.Emit(OpCodes.Stloc, locList);
// hasRows = true
gen.Emit(OpCodes.Ldc_I4_1);
gen.Emit(OpCodes.Stloc, locHasRows);
// start loop
Label labLoopTest = gen.DefineLabel();
Label labLoopTop = gen.DefineLabel();
LocalBuilder locI = gen.DeclareLocal(typeof(int));
gen.Emit(OpCodes.Ldc_I4_0);
gen.Emit(OpCodes.Stloc, locI);
gen.Emit(OpCodes.Br, labLoopTest);
gen.MarkLabel(labLoopTop);
// loop interior
// if (i > 0 && hasRows) { hasRows = this.Read(); }
gen.Emit(OpCodes.Ldloc, locI);
gen.Emit(OpCodes.Ldc_I4_0);
gen.Emit(OpCodes.Cgt);
gen.Emit(OpCodes.Ldloc, locHasRows);
gen.Emit(OpCodes.And);
Label labNext = gen.DefineLabel();
gen.Emit(OpCodes.Brfalse, labNext);
// this.Read()
gen.Emit(OpCodes.Ldarg_0);
Type orbType = typeof(ObjectMaterializer<>).MakeGenericType(this.compiler.DataReaderType);
MethodInfo miRead = orbType.GetMethod("Read", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, null, Type.EmptyTypes, null);
Diagnostics.Debug.Assert(miRead != null);
gen.Emit(GetMethodCallOpCode(miRead), miRead);
gen.Emit(OpCodes.Stloc, locHasRows);
gen.MarkLabel(labNext);
// if (hasRows) { list.Add(expr); }
Label labNext2 = gen.DefineLabel();
gen.Emit(OpCodes.Ldloc, locHasRows);
gen.Emit(OpCodes.Brfalse, labNext2);
gen.Emit(OpCodes.Ldloc, locList);
this.GenerateExpressionForType(jc.Expression, joinElementType);
MethodInfo miAdd = listType.GetMethod("Add", BindingFlags.Instance | BindingFlags.Public, null, new Type[] { joinElementType }, null);
Diagnostics.Debug.Assert(miAdd != null);
gen.Emit(GetMethodCallOpCode(miAdd), miAdd);
gen.MarkLabel(labNext2);
// loop bottom
// i = i + 1
gen.Emit(OpCodes.Ldloc, locI);
gen.Emit(OpCodes.Ldc_I4_1);
gen.Emit(OpCodes.Add);
gen.Emit(OpCodes.Stloc, locI);
// loop test
// i < count && hasRows
gen.MarkLabel(labLoopTest);
gen.Emit(OpCodes.Ldloc, locI);
gen.Emit(OpCodes.Ldloc, locCount);
gen.Emit(OpCodes.Clt);
gen.Emit(OpCodes.Ldloc, locHasRows);
gen.Emit(OpCodes.And);
gen.Emit(OpCodes.Brtrue, labLoopTop);
// return list;
gen.Emit(OpCodes.Ldloc, locList);
return listType;
}
internal override SqlExpression VisitJoinedCollection(SqlJoinedCollection jc)
{
if(!_isDebugMode)
{
throw Error.InvalidFormatNode("JoinedCollection");
}
_commandStringBuilder.Append("big-join(");
this.Visit(jc.Expression);
_commandStringBuilder.Append(", ");
this.Visit(jc.Count);
_commandStringBuilder.Append(")");
return jc;
}
internal override SqlExpression VisitJoinedCollection(SqlJoinedCollection jc)
{
return new SqlJoinedCollection(jc.ClrType, jc.SqlType, this.VisitExpression(jc.Expression), this.VisitExpression(jc.Count), jc.SourceExpression);
}
