protected override DbColumnAssignment VisitColumnAssignment(DbColumnAssignment ca) { ca = base.VisitColumnAssignment(ca); Expression expression = ca.Expression; DbNamedValueExpression nv = expression as DbNamedValueExpression; if (nv != null) { expression = new DbNamedValueExpression(nv.Name, ca.Column.DbType, nv.Value); } return(this.UpdateColumnAssignment(ca, ca.Column, expression)); }
protected override Expression VisitMemberAccess(MemberExpression m) { m = (MemberExpression)base.VisitMemberAccess(m); DbNamedValueExpression nv = m.Expression as DbNamedValueExpression; if (nv != null) { Expression x = Expression.MakeMemberAccess(nv.Value, m.Member); return(GetNamedValue(x)); } return(m); }
private Expression GetNamedValue(Expression e) { DbNamedValueExpression nv; HashedExpression he = new HashedExpression(e); if (!this.pmap.TryGetValue(he, out nv)) { string name = "p" + (iParam++); nv = new DbNamedValueExpression(name, this.language.TypeSystem.GetColumnType(e.Type), e); this.pmap.Add(he, nv); } return(nv); }
protected override Expression VisitColumn(DbColumnExpression column) { if (column.Alias == this.outerAlias) { DbNamedValueExpression nv; if (!this.map.TryGetValue(column, out nv)) { nv = new DbNamedValueExpression("n" + (iParam++), column.DbType, column); this.map.Add(column, nv); } return(nv); } return(column); }
protected override Expression VisitConstant(ConstantExpression c) { if (c.Value != null && !IsNumeric(c.Value.GetType())) { DbNamedValueExpression nv; if (!this.map.TryGetValue(c.Value, out nv)) // re-use same name-value if same value { string name = "p" + (iParam++); nv = new DbNamedValueExpression(name, this.language.TypeSystem.GetColumnType(c.Type), c); this.map.Add(c.Value, nv); } return(nv); } return(c); }
protected override Expression VisitBinary(BinaryExpression b) { Expression left = this.Visit(b.Left); Expression right = this.Visit(b.Right); if (left.NodeType == (ExpressionType)DbExpressionType.NamedValue && right.NodeType == (ExpressionType)DbExpressionType.Column) { DbNamedValueExpression nv = (DbNamedValueExpression)left; DbColumnExpression c = (DbColumnExpression)right; left = new DbNamedValueExpression(nv.Name, c.DbType, nv.Value); } else if (b.Right.NodeType == (ExpressionType)DbExpressionType.NamedValue && b.Left.NodeType == (ExpressionType)DbExpressionType.Column) { DbNamedValueExpression nv = (DbNamedValueExpression)right; DbColumnExpression c = (DbColumnExpression)left; right = new DbNamedValueExpression(nv.Name, c.DbType, nv.Value); } return(this.UpdateBinary(b, left, right, b.Conversion, b.IsLiftedToNull, b.Method)); }
protected override Expression VisitDeclaration(DbDeclaration decl) { if (decl.Source != null) { // make query that returns all these declared values as an object[] var projection = new DbProjectionExpression( decl.Source, Expression.NewArrayInit( typeof(object), decl.Variables.Select(v => v.Expression.Type.IsValueType ? Expression.Convert(v.Expression, typeof(object)) : v.Expression).ToArray() ), Aggregator.Aggregate(typeof(object[]), typeof(IEnumerable <object[]>)) ); // create execution variable to hold the array of declared variables var vars = Expression.Parameter(typeof(object[]), "vars"); this.variables.Add(vars); this.initializers.Add(Expression.Constant(null, typeof(object[]))); // create subsitution for each variable (so it will find the variable value in the new vars array) for (int i = 0, n = decl.Variables.Count; i < n; i++) { var v = decl.Variables[i]; DbNamedValueExpression nv = new DbNamedValueExpression( v.Name, v.DbType, Expression.Convert(Expression.ArrayIndex(vars, Expression.Constant(i)), v.Expression.Type) ); this.variableMap.Add(v.Name, nv); } // make sure the execution of the select stuffs the results into the new vars array return(MakeAssign(vars, this.Visit(projection))); } // probably bad if we get here since we must not allow mulitple commands throw new InvalidOperationException("Declaration query not allowed for this langauge"); }
protected virtual Expression VisitNamedValue(DbNamedValueExpression value) { return value; }
protected virtual bool CompareNamedValue(DbNamedValueExpression a, DbNamedValueExpression b) { return(a.Name == b.Name && Compare(a.Value, b.Value)); }
protected override Expression VisitNamedValue(DbNamedValueExpression value) { this.namedValues.Add(value); return(value); }
protected override Expression VisitNamedValue(DbNamedValueExpression value) { this.WriteParameterName(value.Name); return value; }
protected virtual bool CompareNamedValue(DbNamedValueExpression a, DbNamedValueExpression b) { return a.Name == b.Name && Compare(a.Value, b.Value); }
protected virtual Expression VisitNamedValue(DbNamedValueExpression value) { return(value); }