Change option from 0 to 1 for InStr. Make it use vbTextCompare which is case insensitive

src/EFCore.Jet/Query/ExpressionTranslators/Internal/JetMathTranslator.cs

@@ -84,8 +84,8 @@ namespace EntityFrameworkCore.Jet.Query.ExpressionTranslators.Internal
                 return _sqlExpressionFactory.Function(
                     sqlFunctionName,
                     arguments,
-                    false,
-                    new[] {false},
+                    true,
+                    new[] {true},
                     method.ReturnType);
             }
 
@@ -121,8 +121,8 @@ namespace EntityFrameworkCore.Jet.Query.ExpressionTranslators.Internal
                                     )
                                 )
                             },
-                            false,
-                            new[] {false},
+                            true,
+                            new[] {true},
                             method.ReturnType)),
 
                     // Arcsin(X) = Atn(X / Sqr(-X * X + 1))
@@ -151,20 +151,20 @@ namespace EntityFrameworkCore.Jet.Query.ExpressionTranslators.Internal
                                 )
                             )
                         },
-                        false,
-                        new[] {false},
+                        true,
+                        new[] {true},
                         method.ReturnType),
 
                     // Logn(x) = Log(x) / Log(n)
                     nameof(Math.Log10) => _sqlExpressionFactory.Divide(
-                        _sqlExpressionFactory.Function("LOG", new[] {arguments[0]}, false, new[] {false}, method.ReturnType),
+                        _sqlExpressionFactory.Function("LOG", new[] {arguments[0]}, true, new[] {true}, method.ReturnType),
                         _sqlExpressionFactory.Constant(Math.Log(10))
                     ),
 
                     // Math.Log(x, n) //Logn(x) = Log(x) / Log(n)
                     nameof(Math.Log) => _sqlExpressionFactory.Divide(
-                        _sqlExpressionFactory.Function("LOG", new[] {arguments[0]}, false, new[] {false}, method.ReturnType),
-                        _sqlExpressionFactory.Function("LOG", new[] {arguments[1]}, false, new[] {false}, method.ReturnType)
+                        _sqlExpressionFactory.Function("LOG", new[] {arguments[0]}, true, new[] {true}, method.ReturnType),
+                        _sqlExpressionFactory.Function("LOG", new[] {arguments[1]}, true, new[] {true}, method.ReturnType)
                     ),
 
                     _ => null,
@@ -176,8 +176,8 @@ namespace EntityFrameworkCore.Jet.Query.ExpressionTranslators.Internal
                 return _sqlExpressionFactory.Function(
                     "INT",
                     new[] {arguments[0]},
-                    false,
-                    new[] {false},
+                    true,
+                    new[] {true},
                     method.ReturnType);
             }
 
@@ -188,8 +188,8 @@ namespace EntityFrameworkCore.Jet.Query.ExpressionTranslators.Internal
                     arguments.Count == 1
                         ? new[] {arguments[0], _sqlExpressionFactory.Constant(0)}
                         : new[] {arguments[0], arguments[1]},
-                    false,
-                    new[] {false},
+                    true,
+                    new[] {true},
                     method.ReturnType);
             }
 

src/EFCore.Jet/Query/ExpressionTranslators/Internal/JetStringMethodTranslator.cs

@@ -101,7 +101,7 @@ namespace EntityFrameworkCore.Jet.Query.ExpressionTranslators.Internal
                     || string.Equals(storeType, "varchar(max)", StringComparison.OrdinalIgnoreCase))
                 {
                     charIndexExpression = _sqlExpressionFactory.Function(
-                        "INSTR",
+                        "InStr",
                         new[] { _sqlExpressionFactory.ApplyTypeMapping(instance, stringTypeMapping), argument },
                         nullable: true,
                         argumentsPropagateNullability: new[] { true, true },
@@ -112,7 +112,7 @@ namespace EntityFrameworkCore.Jet.Query.ExpressionTranslators.Internal
                 else
                 {
                     charIndexExpression = _sqlExpressionFactory.Function(
-                        "INSTR",
+                        "InStr",
                         new[] { _sqlExpressionFactory.ApplyTypeMapping(instance, stringTypeMapping), argument },
                         nullable: true,
                         argumentsPropagateNullability: new[] { true, true },
@@ -120,7 +120,17 @@ namespace EntityFrameworkCore.Jet.Query.ExpressionTranslators.Internal
                 }
 
                 charIndexExpression = _sqlExpressionFactory.Subtract(charIndexExpression, _sqlExpressionFactory.Constant(1));
-                return charIndexExpression;
+
+                return _sqlExpressionFactory.Case(
+                    new[]
+                    {
+                            new CaseWhenClause(
+                                _sqlExpressionFactory.Equal(
+                                    instance,
+                                    _sqlExpressionFactory.Constant(string.Empty, stringTypeMapping)),
+                                _sqlExpressionFactory.Constant(0))
+                    },
+                    charIndexExpression);
             }
 
             if (Equals(method, _containsMethodInfo))
@@ -138,7 +148,7 @@ namespace EntityFrameworkCore.Jet.Query.ExpressionTranslators.Internal
                             _sqlExpressionFactory.Constant(1),
                             instance,
                             patternExpression,
-                            _sqlExpressionFactory.Constant(0)
+                            _sqlExpressionFactory.Constant(1)
                         },
                         false,
                         new[] {false},