public virtual ISqlNode VisitCast(SqlCastNode n)
{
var expr = Visit(n.Expression);
var type = Visit(n.DataType) as SqlDataTypeNode;
return(n.Update(expr, type));
}
public void Optimize_CastStringToNumeric()
{
// CAST("123.45" as NUMERIC) => 123.45M
var ast = new SqlCastNode
{
Expression = new SqlStringNode("123.45"),
DataType = new SqlDataTypeNode
{
DataType = new SqlKeywordNode("NUMERIC")
}
};
var target = new ExpressionOptimizeVisitor();
var result = target.Visit(ast);
result.Should().MatchAst(new SqlNumberNode(123.45M));
}
public void Optimize_CastStringToBigint()
{
// CAST("12345" as BIGINT) => 12345L
var ast = new SqlCastNode
{
Expression = new SqlStringNode("12345"),
DataType = new SqlDataTypeNode
{
DataType = new SqlKeywordNode("BIGINT")
}
};
var target = new ExpressionOptimizeVisitor();
var result = target.Visit(ast);
result.Should().MatchAst(new SqlNumberNode(12345L));
}
public void Optimize_CastNumberToVarcharMax()
{
// CAST(5 as VARCHAR(MAX)) => "5"
var ast = new SqlCastNode
{
Expression = new SqlNumberNode(5),
DataType = new SqlDataTypeNode
{
DataType = new SqlKeywordNode("VARCHAR"),
Size = new SqlKeywordNode("MAX")
}
};
var target = new ExpressionOptimizeVisitor();
var result = target.Visit(ast);
result.Should().MatchAst(new SqlStringNode("5"));
}
public void Optimize_CastStringToVarcharNoPadRight()
{
// CAST("12345" as VARCHAR(3)) => "123"
var ast = new SqlCastNode
{
Expression = new SqlStringNode("ab"),
DataType = new SqlDataTypeNode
{
DataType = new SqlKeywordNode("VARCHAR"),
Size = new SqlNumberNode(4)
}
};
var target = new ExpressionOptimizeVisitor();
var result = target.Visit(ast);
result.Should().MatchAst(new SqlStringNode("ab"));
}
public ISqlNode VisitCast(SqlCastNode n)
{
Append("CAST(", n.Expression, " AS ", n.DataType, ")");
return(n);
}
public override ISqlNode VisitCast(SqlCastNode n)
{
return(n.TryReduce());
}