加个接口

helper/func.go

@@ -114,3 +114,9 @@ func GetContextVal[V, K any](ctx context.Context, k K, defaults V) V {
 	}
 	return vv
 }
+
+func IsImplements[T, A any](i A) (T, bool) {
+	var a any = i
+	t, ok := a.(T)
+	return t, ok
+}

helper/slice/slices.go

@@ -71,3 +71,23 @@ func Unshift[T any](a *[]T, e ...T) {
 func Push[T any](a *[]T, e ...T) {
 	*a = append(*a, e...)
 }
+
+func Decompress[T any](a [][]T) (r []T) {
+	for _, ts := range a {
+		for _, t := range ts {
+			r = append(r, t)
+		}
+	}
+	return
+}
+func DecompressBy[T, R any](a [][]T, fn func(T) (R, bool)) (r []R) {
+	for _, ts := range a {
+		for _, t := range ts {
+			v, ok := fn(t)
+			if ok {
+				r = append(r, v)
+			}
+		}
+	}
+	return
+}

model/model.go

@@ -22,6 +22,10 @@ type ParseWhere interface {
 	ParseWhere(*[][]any) (string, []any, error)
 }
 
+type AndWhere interface {
+	AndWhere(field, operator, val, fieldType string) ParseWhere
+}
+
 type dbQuery interface {
 	Select(context.Context, any, string, ...any) error
 	Get(context.Context, any, string, ...any) error

model/parse.go

@@ -186,3 +186,10 @@ func (w SqlBuilder) parseJoin() string {
 	}
 	return s.String()
 }
+
+func (w SqlBuilder) AndWhere(field, operator, val, fieldType string) ParseWhere {
+	ww := append(w, []string{
+		field, operator, val, fieldType,
+	})
+	return ww
+}

model/relation.go

@@ -24,7 +24,7 @@ const (
 
 // Relationship join table
 //
-// RelationType HasOne| HasMany
+// # RelationType HasOne| HasMany
 //
 // eg: hasOne, post has a user. ForeignKey is user's id , Local is post's userId field
 //
@@ -90,6 +90,18 @@ func parseAfterJoin(fromTable string, ids [][]any, qq *QueryCondition, ship Rela
 				tables[len(tables)-1], ship.Middle.ForeignKey), "in", ""},
 			)
 			qq.Where = ww
+		} else {
+			aw, ok := helper.IsImplements[AndWhere](qq.Where)
+			if ok {
+				vv := aw.AndWhere(fmt.Sprintf("%s.%s",
+					tables[len(tables)-1], ship.Middle.ForeignKey), "in", strings.Join(slice.DecompressBy(ids, func(t any) (string, bool) {
+					return fmt.Sprintf("%v", t), true
+				}), ","), "int")
+				wa, ok := helper.IsImplements[ParseWhere](vv)
+				if ok {
+					qq.Where = wa
+				}
+			}
 		}
 		if qq.Fields == "" || qq.Fields == "*" {
 			qq.Fields = str.Join(from[len(from)-1], ".", "*", ",", tables[len(tables)-1], ".", ship.Middle.ForeignKey)
@@ -133,18 +145,26 @@ func Relation(isPlural bool, db dbQuery, ctx context.Context, r any, q *QueryCon
 			if w == nil {
 				qq.Where = SqlBuilder{}
 			}
-			ww, ok := qq.Where.(SqlBuilder)
 			in := [][]any{ids}
-			if ok {
-				if ship.Middle != nil {
-					isPlural = parseAfterJoin(qq.From, in, qq, ship)
-				} else {
+			if ship.Middle != nil {
+				isPlural = parseAfterJoin(qq.From, in, qq, ship)
+			} else {
+				ww, ok := qq.Where.(SqlBuilder)
+				if ok {
 					ww = append(ww, SqlBuilder{{
 						ship.ForeignKey, "in", "",
 					}}...)
-					qq.In = in
 					qq.Where = ww
+				} else {
+					aw, ok := helper.IsImplements[AndWhere](qq.Where)
+					if ok {
+						ww := aw.AndWhere(ship.ForeignKey, "in", strings.Join(slice.Map(ids, func(t any) string {
+							return fmt.Sprintf("%v", t)
+						}), ","), "int")
+						qq.Where = ww
+					}
 				}
+				qq.In = in
 			}
 			err = ParseRelation(isPlural || ship.RelationType == HasMany, db, ctx, helper.Or(isPlural, rrs, rr), qq)
 			if err != nil {