代码调整

FreeSql/DataAnnotations/TableAttribute.cs

@@ -17,6 +17,6 @@ namespace FreeSql.DataAnnotations {
 		/// </summary>
 		public string SelectFilter { get; set; }
 
-		internal ConcurrentDictionary<string, ColumnAttribute> _columns = new ConcurrentDictionary<string, ColumnAttribute>(StringComparer.CurrentCultureIgnoreCase);
+		internal ConcurrentDictionary<string, ColumnAttribute> _columns => new ConcurrentDictionary<string, ColumnAttribute>(StringComparer.CurrentCultureIgnoreCase);
 	}
 }

FreeSql/Extensions/FreeSqlGlobalExtensions.cs

@@ -26,6 +26,7 @@ public static class FreeSqlGlobalExtensions {
 		[typeof(decimal)] = true, [typeof(decimal?)] = true
 	});
 	public static bool IsNumberType(this Type that) => that == null ? false : dicIsNumberType.Value.ContainsKey(that);
+	public static bool IsNullableType(this Type that) => that?.FullName.StartsWith("System.Nullable`1[") == true;
 
 	/// <summary>
 	/// 测量两个经纬度的距离，返回单位：米

FreeSql/Internal/CommonExpression.cs

@@ -299,7 +299,7 @@ namespace FreeSql.Internal {
 					throw new Exception($"未现实函数表达式 {exp3} 解析");
 				case ExpressionType.MemberAccess:
 					var exp4 = exp as MemberExpression;
-					if (exp4.Expression != null && exp4.Expression.Type.IsArray == false && exp4.Expression.Type.FullName.StartsWith("System.Nullable`1[")) return ExpressionLambdaToSql(exp4.Expression, _tables, _selectColumnMap, getSelectGroupingMapString, tbtype, isQuoteName);
+					if (exp4.Expression != null && exp4.Expression.Type.IsArray == false && exp4.Expression.Type.IsNullableType()) return ExpressionLambdaToSql(exp4.Expression, _tables, _selectColumnMap, getSelectGroupingMapString, tbtype, isQuoteName);
 					var extRet = "";
 					var memberType = exp4.Expression?.Type ?? exp4.Type;
 					switch (memberType.FullName) {

FreeSql/Internal/CommonProvider/SelectProvider/Select0Provider.cs

@@ -249,7 +249,7 @@ namespace FreeSql.Internal.CommonProvider {
 			public Func<DbDataReader, T1> Read { get; set; }
 		}
 		protected GetAllFieldExpressionTreeInfo GetAllFieldExpressionTree() {
-			return _dicGetAllFieldExpressionTree.GetOrAdd(string.Join("+", _tables.Select(a => $"{a.Table.DbName}-{a.Alias}-{a.Type}")), s => {
+			return _dicGetAllFieldExpressionTree.GetOrAdd(string.Join("+", _tables.Select(a => $"{_commonUtils.DbName}-{a.Table.DbName}-{a.Alias}-{a.Type}")), s => {
 				var tb1 = _tables.First().Table;
 				var type = tb1.TypeLazy ?? tb1.Type;
 				var props = tb1.Properties;
@@ -313,7 +313,7 @@ namespace FreeSql.Internal.CommonProvider {
 					);
 					else {
 						var proptypeGeneric = prop.PropertyType;
-						if (proptypeGeneric.FullName.StartsWith("System.Nullable`1[")) proptypeGeneric = proptypeGeneric.GenericTypeArguments.First();
+						if (proptypeGeneric.IsNullableType()) proptypeGeneric = proptypeGeneric.GenericTypeArguments.First();
 						if (proptypeGeneric.IsEnum ||
 							Utils.dicExecuteArrayRowReadClassOrTuple.ContainsKey(proptypeGeneric)) readExpAssign = Expression.New(Utils.RowInfo.Constructor,
 								Utils.GetDataReaderValueBlockExpression(prop.PropertyType, Expression.Call(rowExp, Utils.MethodDataReaderGetValue, dataIndexExp)),

FreeSql/Internal/UtilsExpressionTree.cs

@@ -85,11 +85,9 @@ namespace FreeSql.Internal {
 				});
 				colattr.DbDefautValue = trytb.Properties[p.Name].GetValue(Activator.CreateInstance(trytb.Type));
 				if (colattr.DbDefautValue == null) colattr.DbDefautValue = tp?.defaultValue;
-				if (colattr.IsNullable == false && colattr.DbDefautValue == null) {
+				if (colattr.IsNullable == false && colattr.DbDefautValue == null)
-					var consturctorType = p.PropertyType.GenericTypeArguments.FirstOrDefault() ?? p.PropertyType;
+					colattr.DbDefautValue = Activator.CreateInstance(p.PropertyType.IsNullableType() ? p.PropertyType.GenericTypeArguments.FirstOrDefault() : p.PropertyType);
-					colattr.DbDefautValue = Activator.CreateInstance(consturctorType);
+				if (colattr.IsIdentity == true && p.PropertyType.IsNumberType() == false)
-				}
-				if (colattr.IsIdentity == true && (p.PropertyType.GenericTypeArguments.FirstOrDefault() ?? p.PropertyType)?.IsNumberType() == false)
 					colattr.IsIdentity = false;
 
 				var col = new ColumnInfo {
@@ -538,7 +536,7 @@ namespace FreeSql.Internal {
 					), new[] { typeExp, indexesExp, rowExp, dataIndexExp }).Compile();
 
 				var typeGeneric = type;
-				if (typeGeneric.FullName.StartsWith("System.Nullable`1[")) typeGeneric = type.GenericTypeArguments.First();
+				if (typeGeneric.IsNullableType()) typeGeneric = type.GenericTypeArguments.First();
 				if (typeGeneric.IsEnum ||
 					dicExecuteArrayRowReadClassOrTuple.ContainsKey(typeGeneric))
 					return Expression.Lambda<Func<Type, int[], DbDataReader, int, RowInfo>>(
@@ -567,7 +565,7 @@ namespace FreeSql.Internal {
 							);
 							else {
 								var fieldtypeGeneric = field.FieldType;
-								if (fieldtypeGeneric.FullName.StartsWith("System.Nullable`1[")) fieldtypeGeneric = fieldtypeGeneric.GenericTypeArguments.First();
+								if (fieldtypeGeneric.IsNullableType()) fieldtypeGeneric = fieldtypeGeneric.GenericTypeArguments.First();
 								if (fieldtypeGeneric.IsEnum ||
 									dicExecuteArrayRowReadClassOrTuple.ContainsKey(fieldtypeGeneric)) read2ExpAssign = Expression.New(RowInfo.Constructor,
 										GetDataReaderValueBlockExpression(field.FieldType, Expression.Call(rowExp, MethodDataReaderGetValue, dataIndexExp)),
@@ -653,7 +651,7 @@ namespace FreeSql.Internal {
 						);
 						else {
 							var proptypeGeneric = ctorParm.ParameterType;
-							if (proptypeGeneric.FullName.StartsWith("System.Nullable`1[")) proptypeGeneric = proptypeGeneric.GenericTypeArguments.First();
+							if (proptypeGeneric.IsNullableType()) proptypeGeneric = proptypeGeneric.GenericTypeArguments.First();
 							if (proptypeGeneric.IsEnum ||
 								dicExecuteArrayRowReadClassOrTuple.ContainsKey(proptypeGeneric)) readExpAssign = Expression.New(RowInfo.Constructor,
 									GetDataReaderValueBlockExpression(ctorParm.ParameterType, Expression.Call(rowExp, MethodDataReaderGetValue, dataIndexExp)),
@@ -701,7 +699,7 @@ namespace FreeSql.Internal {
 						);
 						else {
 							var proptypeGeneric = prop.PropertyType;
-							if (proptypeGeneric.FullName.StartsWith("System.Nullable`1[")) proptypeGeneric = proptypeGeneric.GenericTypeArguments.First();
+							if (proptypeGeneric.IsNullableType()) proptypeGeneric = proptypeGeneric.GenericTypeArguments.First();
 							if (proptypeGeneric.IsEnum ||
 								dicExecuteArrayRowReadClassOrTuple.ContainsKey(proptypeGeneric)) readExpAssign = Expression.New(RowInfo.Constructor,
 									GetDataReaderValueBlockExpression(prop.PropertyType, Expression.Call(rowExp, MethodDataReaderGetValue, tryidxExp)),
@@ -825,7 +823,7 @@ namespace FreeSql.Internal {
 						)
 					);
 				}
-				if (type.FullName.StartsWith("System.Nullable`1[")) type = type.GenericTypeArguments.First();
+				if (type.IsNullableType()) type = type.GenericTypeArguments.First();
 				if (type.IsEnum) return Expression.Return(returnTarget, Expression.Call(MethodEnumParse, Expression.Constant(type, typeof(Type)), Expression.Call(MethodToString, valueExp), Expression.Constant(true, typeof(bool))));
 				switch(type.FullName) {
 					case "System.Guid": return Expression.IfThenElse(
@@ -927,7 +925,7 @@ namespace FreeSql.Internal {
 			//			), parmExp).Compile();
 			//	}
 
-			//	if (type.FullName.StartsWith("System.Nullable`1[")) type = type.GenericTypeArguments.First();
+			//	if (type.IsNullableType()) type = type.GenericTypeArguments.First();
 			//	if (type.IsEnum) return Expression.Lambda<Func<object, object>>(
 			//		Expression.Call(
 			//			MethodEnumParse,
@@ -1020,7 +1018,7 @@ namespace FreeSql.Internal {
 				}
 				return ret;
 			}
-			if (type.FullName.StartsWith("System.Nullable`1[")) type = type.GenericTypeArguments.First();
+			if (type.IsNullableType()) type = type.GenericTypeArguments.First();
 			if (type.IsEnum) return Enum.Parse(type, string.Concat(value), true);
 			switch (type.FullName) {
 				case "System.Guid":

FreeSql/Internal/UtilsReflection.cs

@@ -70,10 +70,8 @@ namespace FreeSql.Internal {
 				});
 				colattr.DbDefautValue = trytb.Properties[p.Name].GetValue(Activator.CreateInstance(trytb.Type));
 				if (colattr.DbDefautValue == null) colattr.DbDefautValue = tp?.defaultValue;
-				if (colattr.IsNullable == false && colattr.DbDefautValue == null) {
+				if (colattr.IsNullable == false && colattr.DbDefautValue == null)
-					var consturctorType = p.PropertyType.GenericTypeArguments.FirstOrDefault() ?? p.PropertyType;
+					colattr.DbDefautValue = Activator.CreateInstance(p.PropertyType.IsNullableType() ? p.PropertyType.GenericTypeArguments.FirstOrDefault() : p.PropertyType);
-					colattr.DbDefautValue = Activator.CreateInstance(consturctorType);
-				}
 
 				var col = new ColumnInfo {
 					Table = trytb,
@@ -177,7 +175,7 @@ namespace FreeSql.Internal {
 		internal static (object value, int dataIndex) ExecuteArrayRowReadClassOrTuple(Type type, Dictionary<string, int> names, object[] row, int dataIndex = 0) {
 			if (type.IsArray) return (GetDataReaderValue(type, row[dataIndex]), dataIndex + 1);
 			var typeGeneric = type;
-			if (typeGeneric.FullName.StartsWith("System.Nullable`1[")) typeGeneric = type.GenericTypeArguments.First();
+			if (typeGeneric.IsNullableType()) typeGeneric = type.GenericTypeArguments.First();
 			if (typeGeneric.IsEnum ||
 				dicExecuteArrayRowReadClassOrTuple.ContainsKey(typeGeneric))
 				return (GetDataReaderValue(type, row[dataIndex]), dataIndex + 1);
@@ -251,7 +249,7 @@ namespace FreeSql.Internal {
 				}
 				return ret;
 			}
-			if (type.FullName.StartsWith("System.Nullable`1[")) type = type.GenericTypeArguments.First();
+			if (type.IsNullableType()) type = type.GenericTypeArguments.First();
 			if (type.IsEnum) return Enum.Parse(type, string.Concat(value), true);
 			switch(type.FullName) {
 				case "System.Guid":

FreeSql/MySql/MySqlCodeFirst.cs

@@ -65,7 +65,7 @@ namespace FreeSql.MySql {
 			if (_dicCsToDb.TryGetValue(type.FullName, out var trydc)) return new (int, string, string, bool?, object)?(((int)trydc.type, trydc.dbtype, trydc.dbtypeFull, trydc.isnullable, trydc.defaultValue));
 			if (type.IsArray) return null;
 			var enumType = type.IsEnum ? type : null;
-			if (enumType == null && type.FullName.StartsWith("System.Nullable`1[") && type.GenericTypeArguments.Length == 1 && type.GenericTypeArguments.First().IsEnum) enumType = type.GenericTypeArguments.First();
+			if (enumType == null && type.IsNullableType() && type.GenericTypeArguments.Length == 1 && type.GenericTypeArguments.First().IsEnum) enumType = type.GenericTypeArguments.First();
 			if (enumType != null) {
 				var names = string.Join(",", Enum.GetNames(enumType).Select(a => _commonUtils.FormatSql("{0}", a)));
 				var newItem = enumType.GetCustomAttributes(typeof(FlagsAttribute), false).Any() ?

FreeSql/MySql/MySqlExpression.cs

@@ -246,10 +246,10 @@ namespace FreeSql.MySql {
 					case "AddTicks": return $"date_add({left}, interval ({args1})/10 microsecond)";
 					case "AddYears": return $"date_add({left}, interval ({args1}) year)";
 					case "Subtract":
-						if (exp.Arguments[0].Type.FullName == "System.DateTime" || exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault()?.FullName == "System.DateTime")
+						switch((exp.Arguments[0].Type.IsNullableType() ? exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault() : exp.Arguments[0].Type).FullName) {
-							return $"timestampdiff(microsecond, {args1}, {left})";
+							case "System.DateTime": return $"timestampdiff(microsecond, {args1}, {left})";
-						if (exp.Arguments[0].Type.FullName == "System.TimeSpan" || exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault()?.FullName == "System.TimeSpan")
+							case "System.TimeSpan": return $"date_sub({left}, interval ({args1}) microsecond)";
-							return $"date_sub({left}, interval ({args1}) microsecond)";
+						}
 						break;
 					case "Equals": return $"({left} = {getExp(exp.Arguments[0])})";
 					case "CompareTo": return $"(({left}) - ({getExp(exp.Arguments[0])}))";

FreeSql/Oracle/OracleCodeFirst.cs

@@ -59,7 +59,7 @@ namespace FreeSql.Oracle {
 			if (_dicCsToDb.TryGetValue(type.FullName, out var trydc)) return new (int, string, string, bool?, object)?(((int)trydc.type, trydc.dbtype, trydc.dbtypeFull, trydc.isnullable, trydc.defaultValue));
 			if (type.IsArray) return null;
 			var enumType = type.IsEnum ? type : null;
-			if (enumType == null && type.FullName.StartsWith("System.Nullable`1[") && type.GenericTypeArguments.Length == 1 && type.GenericTypeArguments.First().IsEnum) enumType = type.GenericTypeArguments.First();
+			if (enumType == null && type.IsNullableType() && type.GenericTypeArguments.Length == 1 && type.GenericTypeArguments.First().IsEnum) enumType = type.GenericTypeArguments.First();
 			if (enumType != null) {
 				var newItem = enumType.GetCustomAttributes(typeof(FlagsAttribute), false).Any() ?
 					(OracleDbType.Int32, "number", $"number(16){(type.IsEnum ? " NOT NULL" : "")}", false, type.IsEnum ? false : true, Enum.GetValues(enumType).GetValue(0)) :

FreeSql/Oracle/OracleExpression.cs

@@ -247,10 +247,10 @@ namespace FreeSql.Oracle {
 					case "AddTicks": return $"({left}+({args1})/864000000000)";
 					case "AddYears": return $"add_months({left},({args1})*12)";
 					case "Subtract":
-						if (exp.Arguments[0].Type.FullName == "System.DateTime" || exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault()?.FullName == "System.DateTime")
+						switch ((exp.Arguments[0].Type.IsNullableType() ? exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault() : exp.Arguments[0].Type).FullName) {
-							return $"({args1}-{left})";
+							case "System.DateTime": return $"({args1}-{left})";
-						if (exp.Arguments[0].Type.FullName == "System.TimeSpan" || exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault()?.FullName == "System.TimeSpan")
+							case "System.TimeSpan": return $"({left}-{args1})";
-							return $"({left}-{args1})";
+						}
 						break;
 					case "Equals": return $"({left} = {getExp(exp.Arguments[0])})";
 					case "CompareTo": return $"extract(day from ({left}-({getExp(exp.Arguments[0])})))";

FreeSql/PostgreSQL/PostgreSQLCodeFirst.cs

@@ -104,7 +104,7 @@ namespace FreeSql.PostgreSQL {
 			if (_dicCsToDb.TryGetValue(type.FullName, out var trydc)) return new (NpgsqlDbType, string, string, bool?, object)?((trydc.type, trydc.dbtype, trydc.dbtypeFull, trydc.isnullable, trydc.defaultValue));
 			if (type.IsArray) return null;
 			var enumType = type.IsEnum ? type : null;
-			if (enumType == null && type.FullName.StartsWith("System.Nullable`1[") && type.GenericTypeArguments.Length == 1 && type.GenericTypeArguments.First().IsEnum) enumType = type.GenericTypeArguments.First();
+			if (enumType == null && type.IsNullableType() && type.GenericTypeArguments.Length == 1 && type.GenericTypeArguments.First().IsEnum) enumType = type.GenericTypeArguments.First();
 			if (enumType != null) {
 				var newItem = enumType.GetCustomAttributes(typeof(FlagsAttribute), false).Any() ?
 					(NpgsqlDbType.Bigint, "int8", $"int8{(type.IsEnum ? " NOT NULL" : "")}", false, type.IsEnum ? false : true, Enum.GetValues(enumType).GetValue(0)) :

FreeSql/PostgreSQL/PostgreSQLExpression.cs

@@ -343,10 +343,10 @@ namespace FreeSql.PostgreSQL {
 					case "AddTicks": return $"(({left})::timestamp+(({args1})/10||' microseconds')::interval)";
 					case "AddYears": return $"(({left})::timestamp+(({args1})||' year')::interval)";
 					case "Subtract":
-						if (exp.Arguments[0].Type.FullName == "System.DateTime" || exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault()?.FullName == "System.DateTime")
+						switch ((exp.Arguments[0].Type.IsNullableType() ? exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault() : exp.Arguments[0].Type).FullName) {
-							return $"(extract(epoch from ({left})::timestamp-({args1})::timestamp)*1000000)";
+							case "System.DateTime": return $"(extract(epoch from ({left})::timestamp-({args1})::timestamp)*1000000)";
-						if (exp.Arguments[0].Type.FullName == "System.TimeSpan" || exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault()?.FullName == "System.TimeSpan")
+							case "System.TimeSpan": return $"(({left})::timestamp-(({args1})||' microseconds')::interval)";
-							return $"(({left})::timestamp-(({args1})||' microseconds')::interval)";
+						}
 						break;
 					case "Equals": return $"({left} = ({getExp(exp.Arguments[0])})::timestamp)";
 					case "CompareTo": return $"extract(epoch from ({left})::timestamp-({getExp(exp.Arguments[0])})::timestamp)";

FreeSql/PostgreSQL/PostgreSQLUtils.cs

@@ -53,13 +53,13 @@ namespace FreeSql.PostgreSQL {
 				var elementType = type.GetElementType();
 				Type enumType = null;
 				if (elementType.IsEnum) enumType = elementType;
-				else if (elementType.FullName.StartsWith("System.Nullable`1[") && elementType.GenericTypeArguments.First().IsEnum) enumType = elementType.GenericTypeArguments.First();
+				else if (elementType.IsNullableType() && elementType.GenericTypeArguments.First().IsEnum) enumType = elementType.GenericTypeArguments.First();
 				if (enumType != null) return enumType.GetCustomAttributes(typeof(FlagsAttribute), false).Any() ?
 					getParamterArrayValue(typeof(long), value, elementType.IsEnum ? null : Enum.GetValues(enumType).GetValue(0)) :
 					getParamterArrayValue(typeof(int), value, elementType.IsEnum ? null : Enum.GetValues(enumType).GetValue(0));
 				return dicGetParamterValue.TryGetValue(type.FullName, out var trydicarr) ? trydicarr(value) : value;
 			}
-			if (type.FullName.StartsWith("System.Nullable`1[")) type = type.GenericTypeArguments.First();
+			if (type.IsNullableType()) type = type.GenericTypeArguments.First();
 			if (type.IsEnum) return (int)value;
 			if (dicGetParamterValue.TryGetValue(type.FullName, out var trydic)) return trydic(value);
 			return value;

FreeSql/SqlServer/SqlServerCodeFirst.cs

@@ -58,7 +58,7 @@ namespace FreeSql.SqlServer {
 			if (_dicCsToDb.TryGetValue(type.FullName, out var trydc)) return new (int, string, string, bool?, object)?(((int)trydc.type, trydc.dbtype, trydc.dbtypeFull, trydc.isnullable, trydc.defaultValue));
 			if (type.IsArray) return null;
 			var enumType = type.IsEnum ? type : null;
-			if (enumType == null && type.FullName.StartsWith("System.Nullable`1[") && type.GenericTypeArguments.Length == 1 && type.GenericTypeArguments.First().IsEnum) enumType = type.GenericTypeArguments.First();
+			if (enumType == null && type.IsNullableType() && type.GenericTypeArguments.Length == 1 && type.GenericTypeArguments.First().IsEnum) enumType = type.GenericTypeArguments.First();
 			if (enumType != null) {
 				var newItem = enumType.GetCustomAttributes(typeof(FlagsAttribute), false).Any() ?
 					(SqlDbType.BigInt, "bigint", $"bigint{(type.IsEnum ? " NOT NULL" : "")}", false, type.IsEnum ? false : true, Enum.GetValues(enumType).GetValue(0)) :

FreeSql/SqlServer/SqlServerExpression.cs

@@ -228,10 +228,10 @@ namespace FreeSql.SqlServer {
 					case "AddTicks": return $"dateadd(second, ({args1})/10000000, {left})";
 					case "AddYears": return $"dateadd(year, {args1}, {left})";
 					case "Subtract":
-						if (exp.Arguments[0].Type.FullName == "System.DateTime" || exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault()?.FullName == "System.DateTime")
+						switch ((exp.Arguments[0].Type.IsNullableType() ? exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault() : exp.Arguments[0].Type).FullName) {
-							return $"datediff(second, {args1}, {left})";
+							case "System.DateTime": return $"datediff(second, {args1}, {left})";
-						if (exp.Arguments[0].Type.FullName == "System.TimeSpan" || exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault()?.FullName == "System.TimeSpan")
+							case "System.TimeSpan": return $"dateadd(second, {args1}*-1, {left})";
-							return $"dateadd(second, {args1}*-1, {left})";
+						}
 						break;
 					case "Equals": return $"({left} = {getExp(exp.Arguments[0])})";
 					case "CompareTo": return $"(({left}) - ({getExp(exp.Arguments[0])}))";

FreeSql/Sqlite/SqliteCodeFirst.cs

@@ -57,7 +57,7 @@ namespace FreeSql.Sqlite {
 			if (_dicCsToDb.TryGetValue(type.FullName, out var trydc)) return new (int, string, string, bool?, object)?(((int)trydc.type, trydc.dbtype, trydc.dbtypeFull, trydc.isnullable, trydc.defaultValue));
 			if (type.IsArray) return null;
 			var enumType = type.IsEnum ? type : null;
-			if (enumType == null && type.FullName.StartsWith("System.Nullable`1[") && type.GenericTypeArguments.Length == 1 && type.GenericTypeArguments.First().IsEnum) enumType = type.GenericTypeArguments.First();
+			if (enumType == null && type.IsNullableType() && type.GenericTypeArguments.Length == 1 && type.GenericTypeArguments.First().IsEnum) enumType = type.GenericTypeArguments.First();
 			if (enumType != null) {
 				var newItem = enumType.GetCustomAttributes(typeof(FlagsAttribute), false).Any() ?
 					(DbType.Int64, "bigint", $"bigint{(type.IsEnum ? " NOT NULL" : "")}", false, type.IsEnum ? false : true, Enum.GetValues(enumType).GetValue(0)) :

FreeSql/Sqlite/SqliteExpression.cs

@@ -251,10 +251,10 @@ namespace FreeSql.Sqlite {
 					case "AddTicks": return $"datetime({left},(({args1})/10000000)||' seconds')";
 					case "AddYears": return $"datetime({left},({args1})||' years')";
 					case "Subtract":
-						if (exp.Arguments[0].Type.FullName == "System.DateTime" || exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault()?.FullName == "System.DateTime")
+						switch ((exp.Arguments[0].Type.IsNullableType() ? exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault() : exp.Arguments[0].Type).FullName) {
-							return $"(strftime('%s',{left})-strftime('%s',{args1}))";
+							case "System.DateTime": return $"(strftime('%s',{left})-strftime('%s',{args1}))";
-						if (exp.Arguments[0].Type.FullName == "System.TimeSpan" || exp.Arguments[0].Type.GenericTypeArguments.FirstOrDefault()?.FullName == "System.TimeSpan")
+							case "System.TimeSpan": return $"datetime({left},(-{args1})||' seconds')";
-							return $"datetime({left},(-{args1})||' seconds')";
+						}
 						break;
 					case "Equals": return $"({left} = {getExp(exp.Arguments[0])})";
 					case "CompareTo": return $"(strftime('%s',{left})-strftime('%s',{args1}))";