protected Expression VisitJetConvertExpression(SqlUnaryExpression convertExpression)
{
var typeMapping = convertExpression.TypeMapping;
if (typeMapping == null)
{
throw new InvalidOperationException(RelationalStrings.UnsupportedType(convertExpression.Type.ShortDisplayName()));
}
if (_convertMappings.TryGetValue(typeMapping.ClrType.Name, out var function))
{
Visit(
_sqlExpressionFactory.NullChecked(
convertExpression.Operand,
_sqlExpressionFactory.Function(
function,
new[] { convertExpression.Operand },
typeMapping.ClrType)));
return(convertExpression);
}
if (typeMapping.ClrType.Name == nameof(String))
{
Sql.Append("(");
Visit(convertExpression.Operand);
Sql.Append(@" & '')");
return(convertExpression);
}
throw new InvalidOperationException($"Cannot cast to CLR type '{typeMapping.ClrType.Name}' with Jet.");
}
protected Expression VisitJetConvertExpression(SqlUnaryExpression convertExpression)
{
var typeMapping = convertExpression.TypeMapping;
if (typeMapping == null)
{
throw new InvalidOperationException(RelationalStrings.UnsupportedType(convertExpression.Type.ShortDisplayName()));
}
// We are explicitly converting to the target type (convertExpression.Type) and not the CLR type of the
// accociated type mapping. This allows for conversions on the database side (e.g. CDBL()) but handling
// of the returned value using a different (unaligned) type mapping (e.g. date/time related ones).
if (_convertMappings.TryGetValue(convertExpression.Type.Name, out var function))
{
Visit(
_sqlExpressionFactory.NullChecked(
convertExpression.Operand,
_sqlExpressionFactory.Function(
function,
new[] { convertExpression.Operand },
false,
new[] { false },
typeMapping.ClrType)));
return(convertExpression);
}
if (typeMapping.ClrType.Name == nameof(String))
{
Sql.Append("(");
Visit(convertExpression.Operand);
Sql.Append(@" & '')");
return(convertExpression);
}
throw new InvalidOperationException($"Cannot cast to CLR type '{typeMapping.ClrType.Name}' with Jet.");
}
