db middle table

model/parse.go

@@ -88,6 +88,7 @@ func (w SqlBuilder) ParseWhere(in *[][]any) (string, []any, error) {
 			args = append(args, ss[1])
 		case 3, 4:
 			w.parseWhereField(ss, &s)
+			s.WriteString(" ")
 			s.WriteString(ss[1])
 			if w.parseIn(ss, &s, &c, &args, in) {
 				s.WriteString(" and ")

model/query_test.go

@@ -39,6 +39,7 @@ type post struct {
 	CommentCount        int64     `gorm:"column:comment_count" db:"comment_count" json:"comment_count" form:"comment_count"`
 	User                *user
 	PostMeta            *[]models.PostMeta
+	TermTaxonomy        *[]models.TermTaxonomy
 }
 
 type TermRelationships struct {

model/relation.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"github.com/fthvgb1/wp-go/helper"
 	"github.com/fthvgb1/wp-go/helper/slice"
+	str "github.com/fthvgb1/wp-go/helper/strings"
 	"golang.org/x/exp/constraints"
 	"strings"
 )
@@ -36,25 +37,88 @@ type Relationship struct {
 	ForeignKey   string
 	Local        string
 	On           string
+	Middle       *Relationship
+}
+
+func parseBeforeJoin(qq *QueryCondition, ship Relationship) {
+	var fromTable, foreignKey, local string
+	if ship.Middle != nil {
+		parseBeforeJoin(qq, *ship.Middle)
+		fromTable = ship.Middle.Table
+		foreignKey = ship.ForeignKey
+		local = ship.Local
+	} else {
+		fromTable = qq.From
+		if ship.RelationType == HasMany {
+			foreignKey = ship.Local
+			local = ship.ForeignKey
+		} else {
+			foreignKey = ship.ForeignKey
+			local = ship.Local
+		}
+	}
+	tables := strings.Split(ship.Table, " ")
+	from := strings.Split(fromTable, " ")
+	on := ""
+	if ship.On != "" {
+		on = fmt.Sprintf("and %s", on)
+	}
+	qq.Join = append(qq.Join, []string{
+		"left join", ship.Table,
+		fmt.Sprintf("%s.%s=%s.%s %s",
+			tables[len(tables)-1], foreignKey, from[len(from)-1], local, on,
+		)})
+
+}
+
+func parseAfterJoin(ids [][]any, qq *QueryCondition, ship Relationship) bool {
+	tables := strings.Split(ship.Middle.Table, " ")
+	from := strings.Split(qq.From, " ")
+	on := ""
+	if ship.On != "" {
+		on = fmt.Sprintf("and %s", on)
+	}
+	foreignKey := ship.ForeignKey
+	local := ship.Local
+	if ship.RelationType == HasMany {
+		foreignKey = ship.Local
+		local = ship.ForeignKey
+	}
+	qq.Join = append(qq.Join, []string{
+		"left join", ship.Middle.Table,
+		fmt.Sprintf("%s.%s=%s.%s %s",
+			tables[len(tables)-1], foreignKey, from[len(from)-1], local, on,
+		),
+	})
+	if ship.Middle.Middle != nil {
+		return parseAfterJoin(ids, qq, *ship.Middle.Middle)
+	} else {
+		ww, ok := qq.Where.(SqlBuilder)
+		if ok {
+			ww = append(ww, []string{fmt.Sprintf("%s.%s",
+				tables[len(tables)-1], ship.Middle.Local), "in", ""},
+			)
+			qq.Where = ww
+		}
+		if qq.Fields == "" || qq.Fields == "*" {
+			qq.Fields = str.Join(from[len(from)-1], ".", "*")
+		}
+		qq.In = ids
+		return ship.Middle.RelationType == HasMany
+	}
 }
 
 func Relation(isPlural bool, db dbQuery, ctx context.Context, r any, q *QueryCondition) ([]func(), []func() error) {
 	var beforeFn []func()
 	var afterFn []func() error
+	qx := helper.GetContextVal(ctx, "ancestorsQueryCondition", q)
+
 	for _, f := range q.RelationFn {
 		getVal, isJoin, qq, relationship := f()
 		idFn, assignmentFn, rr, rrs, ship := relationship()
 		if isJoin {
 			beforeFn = append(beforeFn, func() {
-				tables := strings.Split(ship.Table, " ")
-				from := strings.Split(q.From, " ")
-				on := ""
-				if ship.On != "" {
-					on = fmt.Sprintf("and %s", on)
-				}
-				qq := helper.GetContextVal(ctx, "ancestorsQueryCondition", q)
-				qq.Join = append(qq.Join, []string{
-					"left join", ship.Table, fmt.Sprintf("%s.%s=%s.%s %s", tables[len(tables)-1], ship.ForeignKey, from[len(from)-1], ship.Local, on)})
+				parseBeforeJoin(qx, ship)
 			})
 		}
 		if !getVal {
@@ -71,21 +135,27 @@ func Relation(isPlural bool, db dbQuery, ctx context.Context, r any, q *QueryCon
 					Fields: "*",
 				}
 			}
-			var w any = qq.Where
-			if w == nil {
-				w = SqlBuilder{}
-			}
-			ww, ok := w.(SqlBuilder)
-			if ok {
-				ww = append(ww, SqlBuilder{{
-					ship.ForeignKey, "in", "",
-				}}...)
-				qq.In = [][]any{ids}
-				qq.Where = ww
-			}
 			if qq.From == "" {
 				qq.From = ship.Table
 			}
+			var w any = qq.Where
+			if w == nil {
+				qq.Where = SqlBuilder{}
+			}
+			ww, ok := qq.Where.(SqlBuilder)
+			in := [][]any{ids}
+			if ok {
+				if ship.Middle != nil {
+					isPlural = parseAfterJoin(in, qq, ship)
+				} else {
+					ww = append(ww, SqlBuilder{{
+						ship.ForeignKey, "in", "",
+					}}...)
+					qq.In = in
+					qq.Where = ww
+				}
+			}
+
 			err = ParseRelation(isPlural || ship.RelationType == HasMany, db, ctx, helper.Or(isPlural, rrs, rr), qq)
 			if err != nil {
 				if err == sql.ErrNoRows {
@@ -166,7 +236,9 @@ func SetHasMany[T, V any, K comparable](assignmentFn func(*T, *[]V), pIdFn func(
 
 // RelationHasOne
 // eg: post has a user. fId is post's userId, pId is user's id
-func RelationHasOne[M, P any, I constraints.Integer | uint64](fId func(*M) I, pId func(*P) I, setVal func(*M, *P), r Relationship) RelationFn {
+func RelationHasOne[M, P any, I constraints.Integer | constraints.Unsigned](
+	fId func(*M) I, pId func(*P) I, setVal func(*M, *P), r Relationship) RelationFn {
+
 	idFn := GetWithID(fId)
 	setFn := SetHasOne(setVal, fId, pId)
 	return func() (func(any) []any, func(any, any), any, any, Relationship) {
@@ -178,7 +250,9 @@ func RelationHasOne[M, P any, I constraints.Integer | uint64](fId func(*M) I, pI
 
 // RelationHasMany
 // eg: post has many comments,mId is comment's postId, pId is post's id
-func RelationHasMany[M, P any, I constraints.Integer | uint64](mId func(*M) I, pId func(*P) I, setVal func(*M, *[]P), r Relationship) RelationFn {
+func RelationHasMany[M, P any, I constraints.Integer | constraints.Unsigned](
+	mId func(*M) I, pId func(*P) I, setVal func(*M, *[]P), r Relationship) RelationFn {
+
 	idFn := GetWithID(mId)
 	setFn := SetHasMany(setVal, mId, pId)
 	return func() (func(any) []any, func(any, any), any, any, Relationship) {

model/relation_test.go

@@ -60,6 +60,25 @@ func PostMetas() (func(any) []any, func(any, any), any, any, Relationship) {
 		}
 }
 
+var term = RelationHasMany(func(m *post) uint64 {
+	return m.Id
+}, func(p *models.TermTaxonomy) uint64 {
+	return p.TermTaxonomyId
+}, func(m *post, i *[]models.TermTaxonomy) {
+	m.TermTaxonomy = i
+}, Relationship{
+	RelationType: HasOne,
+	Table:        "wp_term_taxonomy taxonomy",
+	ForeignKey:   "term_taxonomy_id",
+	Local:        "term_taxonomy_id",
+	Middle: &Relationship{
+		RelationType: HasMany,
+		Table:        "wp_term_relationships",
+		ForeignKey:   "ID",
+		Local:        "object_id",
+	},
+})
+
 func Meta2() RelationFn {
 	return RelationHasMany(postId, metasPostId, func(m *post, i *[]models.PostMeta) {
 		m.PostMeta = i
@@ -93,7 +112,8 @@ func TestGets2(t *testing.T) {
 				), PostAuthor2()),
 				Fields("posts.*"),
 				From("wp_posts posts"),
-				WithFn(true, true, nil, Meta2()),
+				WithFn(true, false, nil, Meta2()),
+				WithFn(true, false, nil, term),
 			)
 			got, err := Gets[post](ctx, q)
 			_ = got
@@ -106,7 +126,7 @@ func TestGets2(t *testing.T) {
 		{
 			q := Conditions(
 				Where(SqlBuilder{{"posts.id", "in", ""}}),
-				In([]any{190, 3022}),
+				In([]any{190, 3022, 291}),
 				WithCtx(&ctx),
 				WithFn(true, false, Conditions(
 					Fields("ID,user_login,user_pass"),
@@ -114,6 +134,7 @@ func TestGets2(t *testing.T) {
 				Fields("posts.*"),
 				From("wp_posts posts"),
 				WithFn(true, false, nil, Meta2()),
+				WithFn(true, false, nil, term),
 			)
 			got, err := Finds[post](ctx, q)
 			_ = got