/// <inheritdoc />
protected override Expression VisitBinary(BinaryExpression binaryExpression)
{
// Support DateTime subtraction, which returns a TimeSpan.
if (binaryExpression.NodeType == ExpressionType.Subtract &&
binaryExpression.Left.Type.UnwrapNullableType() == typeof(DateTime) &&
binaryExpression.Left.Type.UnwrapNullableType() == typeof(DateTime))
{
if (TranslationFailed(binaryExpression.Left, Visit(TryRemoveImplicitConvert(binaryExpression.Left)), out var sqlLeft) ||
TranslationFailed(binaryExpression.Right, Visit(TryRemoveImplicitConvert(binaryExpression.Right)), out var sqlRight))
{
return(null);
}
var inferredDateTimeTypeMapping = ExpressionExtensions.InferTypeMapping(sqlLeft, sqlRight);
return(new SqlBinaryExpression(
ExpressionType.Subtract,
_sqlExpressionFactory.ApplyTypeMapping(sqlLeft, inferredDateTimeTypeMapping),
_sqlExpressionFactory.ApplyTypeMapping(sqlRight, inferredDateTimeTypeMapping),
typeof(TimeSpan),
null));
}
if (binaryExpression.NodeType == ExpressionType.ArrayIndex)
{
if (TranslationFailed(binaryExpression.Left, Visit(TryRemoveImplicitConvert(binaryExpression.Left)), out var sqlLeft) ||
TranslationFailed(binaryExpression.Right, Visit(TryRemoveImplicitConvert(binaryExpression.Right)), out var sqlRight))
{
return(null);
}
// ArrayIndex over bytea is special, we have to use function rather than subscript
if (binaryExpression.Left.Type == typeof(byte[]))
{
return(_sqlExpressionFactory.Function(
"get_byte",
new[]
{
_sqlExpressionFactory.ApplyDefaultTypeMapping(sqlLeft),
_sqlExpressionFactory.ApplyDefaultTypeMapping(sqlRight)
},
nullable: true,
argumentsPropagateNullability: TrueArrays[2],
typeof(byte),
_typeMappingSource.FindMapping(typeof(byte))
));
}
return
// Try translating ArrayIndex inside json column
(_jsonPocoTranslator.TranslateMemberAccess(sqlLeft, sqlRight, binaryExpression.Type) ??
// Other types should be subscriptable - but PostgreSQL arrays are 1-based, so adjust the index.
_sqlExpressionFactory.ArrayIndex(sqlLeft, GenerateOneBasedIndexExpression(sqlRight)));
}
return(base.VisitBinary(binaryExpression));
}
public virtual SqlExpression?Translate(
SqlExpression?instance,
MethodInfo method,
IReadOnlyList <SqlExpression> arguments,
IDiagnosticsLogger <DbLoggerCategory.Query> logger)
{
if (instance?.Type.IsGenericList() == true && !IsMappedToNonArray(instance))
{
// Translate list[i]. Note that array[i] is translated by NpgsqlSqlTranslatingExpressionVisitor.VisitBinary (ArrayIndex)
if (method.Name == "get_Item" && arguments.Count == 1)
{
return
// Try translating indexing inside json column
(_jsonPocoTranslator.TranslateMemberAccess(instance, arguments[0], method.ReturnType) ??
// Other types should be subscriptable - but PostgreSQL arrays are 1-based, so adjust the index.
_sqlExpressionFactory.ArrayIndex(instance, GenerateOneBasedIndexExpression(arguments[0])));
}
return(TranslateCommon(instance, arguments));
}
if (instance is null && arguments.Count > 0 && arguments[0].Type.IsArrayOrGenericList() && !IsMappedToNonArray(arguments[0]))
{
// Extension method over an array or list
if (method.IsClosedFormOf(Enumerable_SequenceEqual) && arguments[1].Type.IsArray)
{
return(_sqlExpressionFactory.Equal(arguments[0], arguments[1]));
}
return(TranslateCommon(arguments[0], arguments.Slice(1)));
}
if (method.DeclaringType == typeof(string) &&
(method == String_Join1 ||
method == String_Join2 ||
method == String_Join3 ||
method == String_Join4 ||
method.IsClosedFormOf(String_Join_generic1) ||
method.IsClosedFormOf(String_Join_generic2)) &&
!IsMappedToNonArray(arguments[0]))
{
return(_sqlExpressionFactory.Function(
"array_to_string",
new[] { arguments[1], arguments[0], _sqlExpressionFactory.Constant("") },
nullable: true,
argumentsPropagateNullability: TrueArrays[3],
typeof(string)));
}
// Not an array/list
return(null);