gtsocial-umbx

query_select.go (25908B)

---

 package bun
 
 import (
 	"bytes"
 	"context"
 	"database/sql"
 	"errors"
 	"fmt"
 	"strconv"
 	"strings"
 	"sync"
 
 	"github.com/uptrace/bun/dialect"
 
 	"github.com/uptrace/bun/dialect/feature"
 	"github.com/uptrace/bun/internal"
 	"github.com/uptrace/bun/schema"
 )
 
 type union struct {
 	expr  string
 	query *SelectQuery
 }
 
 type SelectQuery struct {
 	whereBaseQuery
 	idxHintsQuery
 
 	distinctOn []schema.QueryWithArgs
 	joins      []joinQuery
 	group      []schema.QueryWithArgs
 	having     []schema.QueryWithArgs
 	order      []schema.QueryWithArgs
 	limit      int32
 	offset     int32
 	selFor     schema.QueryWithArgs
 
 	union []union
 }
 
 var _ Query = (*SelectQuery)(nil)
 
 func NewSelectQuery(db *DB) *SelectQuery {
 	return &SelectQuery{
 		whereBaseQuery: whereBaseQuery{
 			baseQuery: baseQuery{
 				db:   db,
 				conn: db.DB,
 			},
 		},
 	}
 }
 
 func (q *SelectQuery) Conn(db IConn) *SelectQuery {
 	q.setConn(db)
 	return q
 }
 
 func (q *SelectQuery) Model(model interface{}) *SelectQuery {
 	q.setModel(model)
 	return q
 }
 
 func (q *SelectQuery) Err(err error) *SelectQuery {
 	q.setErr(err)
 	return q
 }
 
 // Apply calls the fn passing the SelectQuery as an argument.
 func (q *SelectQuery) Apply(fn func(*SelectQuery) *SelectQuery) *SelectQuery {
 	if fn != nil {
 		return fn(q)
 	}
 	return q
 }
 
 func (q *SelectQuery) With(name string, query schema.QueryAppender) *SelectQuery {
 	q.addWith(name, query, false)
 	return q
 }
 
 func (q *SelectQuery) WithRecursive(name string, query schema.QueryAppender) *SelectQuery {
 	q.addWith(name, query, true)
 	return q
 }
 
 func (q *SelectQuery) Distinct() *SelectQuery {
 	q.distinctOn = make([]schema.QueryWithArgs, 0)
 	return q
 }
 
 func (q *SelectQuery) DistinctOn(query string, args ...interface{}) *SelectQuery {
 	q.distinctOn = append(q.distinctOn, schema.SafeQuery(query, args))
 	return q
 }
 
 //------------------------------------------------------------------------------
 
 func (q *SelectQuery) Table(tables ...string) *SelectQuery {
 	for _, table := range tables {
 		q.addTable(schema.UnsafeIdent(table))
 	}
 	return q
 }
 
 func (q *SelectQuery) TableExpr(query string, args ...interface{}) *SelectQuery {
 	q.addTable(schema.SafeQuery(query, args))
 	return q
 }
 
 func (q *SelectQuery) ModelTableExpr(query string, args ...interface{}) *SelectQuery {
 	q.modelTableName = schema.SafeQuery(query, args)
 	return q
 }
 
 //------------------------------------------------------------------------------
 
 func (q *SelectQuery) Column(columns ...string) *SelectQuery {
 	for _, column := range columns {
 		q.addColumn(schema.UnsafeIdent(column))
 	}
 	return q
 }
 
 func (q *SelectQuery) ColumnExpr(query string, args ...interface{}) *SelectQuery {
 	q.addColumn(schema.SafeQuery(query, args))
 	return q
 }
 
 func (q *SelectQuery) ExcludeColumn(columns ...string) *SelectQuery {
 	q.excludeColumn(columns)
 	return q
 }
 
 //------------------------------------------------------------------------------
 
 func (q *SelectQuery) WherePK(cols ...string) *SelectQuery {
 	q.addWhereCols(cols)
 	return q
 }
 
 func (q *SelectQuery) Where(query string, args ...interface{}) *SelectQuery {
 	q.addWhere(schema.SafeQueryWithSep(query, args, " AND "))
 	return q
 }
 
 func (q *SelectQuery) WhereOr(query string, args ...interface{}) *SelectQuery {
 	q.addWhere(schema.SafeQueryWithSep(query, args, " OR "))
 	return q
 }
 
 func (q *SelectQuery) WhereGroup(sep string, fn func(*SelectQuery) *SelectQuery) *SelectQuery {
 	saved := q.where
 	q.where = nil
 
 	q = fn(q)
 
 	where := q.where
 	q.where = saved
 
 	q.addWhereGroup(sep, where)
 
 	return q
 }
 
 func (q *SelectQuery) WhereDeleted() *SelectQuery {
 	q.whereDeleted()
 	return q
 }
 
 func (q *SelectQuery) WhereAllWithDeleted() *SelectQuery {
 	q.whereAllWithDeleted()
 	return q
 }
 
 //------------------------------------------------------------------------------
 
 func (q *SelectQuery) UseIndex(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addUseIndex(indexes...)
 	}
 	return q
 }
 
 func (q *SelectQuery) UseIndexForJoin(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addUseIndexForJoin(indexes...)
 	}
 	return q
 }
 
 func (q *SelectQuery) UseIndexForOrderBy(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addUseIndexForOrderBy(indexes...)
 	}
 	return q
 }
 
 func (q *SelectQuery) UseIndexForGroupBy(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addUseIndexForGroupBy(indexes...)
 	}
 	return q
 }
 
 func (q *SelectQuery) IgnoreIndex(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addIgnoreIndex(indexes...)
 	}
 	return q
 }
 
 func (q *SelectQuery) IgnoreIndexForJoin(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addIgnoreIndexForJoin(indexes...)
 	}
 	return q
 }
 
 func (q *SelectQuery) IgnoreIndexForOrderBy(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addIgnoreIndexForOrderBy(indexes...)
 	}
 	return q
 }
 
 func (q *SelectQuery) IgnoreIndexForGroupBy(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addIgnoreIndexForGroupBy(indexes...)
 	}
 	return q
 }
 
 func (q *SelectQuery) ForceIndex(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addForceIndex(indexes...)
 	}
 	return q
 }
 
 func (q *SelectQuery) ForceIndexForJoin(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addForceIndexForJoin(indexes...)
 	}
 	return q
 }
 
 func (q *SelectQuery) ForceIndexForOrderBy(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addForceIndexForOrderBy(indexes...)
 	}
 	return q
 }
 
 func (q *SelectQuery) ForceIndexForGroupBy(indexes ...string) *SelectQuery {
 	if q.db.dialect.Name() == dialect.MySQL {
 		q.addForceIndexForGroupBy(indexes...)
 	}
 	return q
 }
 
 //------------------------------------------------------------------------------
 
 func (q *SelectQuery) Group(columns ...string) *SelectQuery {
 	for _, column := range columns {
 		q.group = append(q.group, schema.UnsafeIdent(column))
 	}
 	return q
 }
 
 func (q *SelectQuery) GroupExpr(group string, args ...interface{}) *SelectQuery {
 	q.group = append(q.group, schema.SafeQuery(group, args))
 	return q
 }
 
 func (q *SelectQuery) Having(having string, args ...interface{}) *SelectQuery {
 	q.having = append(q.having, schema.SafeQuery(having, args))
 	return q
 }
 
 func (q *SelectQuery) Order(orders ...string) *SelectQuery {
 	for _, order := range orders {
 		if order == "" {
 			continue
 		}
 
 		index := strings.IndexByte(order, ' ')
 		if index == -1 {
 			q.order = append(q.order, schema.UnsafeIdent(order))
 			continue
 		}
 
 		field := order[:index]
 		sort := order[index+1:]
 
 		switch strings.ToUpper(sort) {
 		case "ASC", "DESC", "ASC NULLS FIRST", "DESC NULLS FIRST",
 			"ASC NULLS LAST", "DESC NULLS LAST":
 			q.order = append(q.order, schema.SafeQuery("? ?", []interface{}{
 				Ident(field),
 				Safe(sort),
 			}))
 		default:
 			q.order = append(q.order, schema.UnsafeIdent(order))
 		}
 	}
 	return q
 }
 
 func (q *SelectQuery) OrderExpr(query string, args ...interface{}) *SelectQuery {
 	q.order = append(q.order, schema.SafeQuery(query, args))
 	return q
 }
 
 func (q *SelectQuery) Limit(n int) *SelectQuery {
 	q.limit = int32(n)
 	return q
 }
 
 func (q *SelectQuery) Offset(n int) *SelectQuery {
 	q.offset = int32(n)
 	return q
 }
 
 func (q *SelectQuery) For(s string, args ...interface{}) *SelectQuery {
 	q.selFor = schema.SafeQuery(s, args)
 	return q
 }
 
 //------------------------------------------------------------------------------
 
 func (q *SelectQuery) Union(other *SelectQuery) *SelectQuery {
 	return q.addUnion(" UNION ", other)
 }
 
 func (q *SelectQuery) UnionAll(other *SelectQuery) *SelectQuery {
 	return q.addUnion(" UNION ALL ", other)
 }
 
 func (q *SelectQuery) Intersect(other *SelectQuery) *SelectQuery {
 	return q.addUnion(" INTERSECT ", other)
 }
 
 func (q *SelectQuery) IntersectAll(other *SelectQuery) *SelectQuery {
 	return q.addUnion(" INTERSECT ALL ", other)
 }
 
 func (q *SelectQuery) Except(other *SelectQuery) *SelectQuery {
 	return q.addUnion(" EXCEPT ", other)
 }
 
 func (q *SelectQuery) ExceptAll(other *SelectQuery) *SelectQuery {
 	return q.addUnion(" EXCEPT ALL ", other)
 }
 
 func (q *SelectQuery) addUnion(expr string, other *SelectQuery) *SelectQuery {
 	q.union = append(q.union, union{
 		expr:  expr,
 		query: other,
 	})
 	return q
 }
 
 //------------------------------------------------------------------------------
 
 func (q *SelectQuery) Join(join string, args ...interface{}) *SelectQuery {
 	q.joins = append(q.joins, joinQuery{
 		join: schema.SafeQuery(join, args),
 	})
 	return q
 }
 
 func (q *SelectQuery) JoinOn(cond string, args ...interface{}) *SelectQuery {
 	return q.joinOn(cond, args, " AND ")
 }
 
 func (q *SelectQuery) JoinOnOr(cond string, args ...interface{}) *SelectQuery {
 	return q.joinOn(cond, args, " OR ")
 }
 
 func (q *SelectQuery) joinOn(cond string, args []interface{}, sep string) *SelectQuery {
 	if len(q.joins) == 0 {
 		q.err = errors.New("bun: query has no joins")
 		return q
 	}
 	j := &q.joins[len(q.joins)-1]
 	j.on = append(j.on, schema.SafeQueryWithSep(cond, args, sep))
 	return q
 }
 
 //------------------------------------------------------------------------------
 
 // Relation adds a relation to the query.
 func (q *SelectQuery) Relation(name string, apply ...func(*SelectQuery) *SelectQuery) *SelectQuery {
 	if len(apply) > 1 {
 		panic("only one apply function is supported")
 	}
 
 	if q.tableModel == nil {
 		q.setErr(errNilModel)
 		return q
 	}
 
 	join := q.tableModel.join(name)
 	if join == nil {
 		q.setErr(fmt.Errorf("%s does not have relation=%q", q.table, name))
 		return q
 	}
 
 	var apply1, apply2 func(*SelectQuery) *SelectQuery
 
 	if len(join.Relation.Condition) > 0 {
 		apply1 = func(q *SelectQuery) *SelectQuery {
 			for _, opt := range join.Relation.Condition {
 				q.addWhere(schema.SafeQueryWithSep(opt, nil, " AND "))
 			}
 
 			return q
 		}
 	}
 
 	if len(apply) == 1 {
 		apply2 = apply[0]
 	}
 
 	join.apply = func(q *SelectQuery) *SelectQuery {
 		if apply1 != nil {
 			q = apply1(q)
 		}
 		if apply2 != nil {
 			q = apply2(q)
 		}
 
 		return q
 	}
 
 	return q
 }
 
 func (q *SelectQuery) forEachInlineRelJoin(fn func(*relationJoin) error) error {
 	if q.tableModel == nil {
 		return nil
 	}
 	return q._forEachInlineRelJoin(fn, q.tableModel.getJoins())
 }
 
 func (q *SelectQuery) _forEachInlineRelJoin(fn func(*relationJoin) error, joins []relationJoin) error {
 	for i := range joins {
 		j := &joins[i]
 		switch j.Relation.Type {
 		case schema.HasOneRelation, schema.BelongsToRelation:
 			if err := fn(j); err != nil {
 				return err
 			}
 			if err := q._forEachInlineRelJoin(fn, j.JoinModel.getJoins()); err != nil {
 				return err
 			}
 		}
 	}
 	return nil
 }
 
 func (q *SelectQuery) selectJoins(ctx context.Context, joins []relationJoin) error {
 	for i := range joins {
 		j := &joins[i]
 
 		var err error
 
 		switch j.Relation.Type {
 		case schema.HasOneRelation, schema.BelongsToRelation:
 			err = q.selectJoins(ctx, j.JoinModel.getJoins())
 		case schema.HasManyRelation:
 			err = j.selectMany(ctx, q.db.NewSelect().Conn(q.conn))
 		case schema.ManyToManyRelation:
 			err = j.selectM2M(ctx, q.db.NewSelect().Conn(q.conn))
 		default:
 			panic("not reached")
 		}
 
 		if err != nil {
 			return err
 		}
 	}
 	return nil
 }
 
 //------------------------------------------------------------------------------
 
 func (q *SelectQuery) Operation() string {
 	return "SELECT"
 }
 
 func (q *SelectQuery) AppendQuery(fmter schema.Formatter, b []byte) (_ []byte, err error) {
 	return q.appendQuery(fmter, b, false)
 }
 
 func (q *SelectQuery) appendQuery(
 	fmter schema.Formatter, b []byte, count bool,
 ) (_ []byte, err error) {
 	if q.err != nil {
 		return nil, q.err
 	}
 
 	fmter = formatterWithModel(fmter, q)
 
 	cteCount := count && (len(q.group) > 0 || q.distinctOn != nil)
 	if cteCount {
 		b = append(b, "WITH _count_wrapper AS ("...)
 	}
 
 	if len(q.union) > 0 {
 		b = append(b, '(')
 	}
 
 	b, err = q.appendWith(fmter, b)
 	if err != nil {
 		return nil, err
 	}
 
 	b = append(b, "SELECT "...)
 
 	if len(q.distinctOn) > 0 {
 		b = append(b, "DISTINCT ON ("...)
 		for i, app := range q.distinctOn {
 			if i > 0 {
 				b = append(b, ", "...)
 			}
 			b, err = app.AppendQuery(fmter, b)
 			if err != nil {
 				return nil, err
 			}
 		}
 		b = append(b, ") "...)
 	} else if q.distinctOn != nil {
 		b = append(b, "DISTINCT "...)
 	}
 
 	if count && !cteCount {
 		b = append(b, "count(*)"...)
 	} else {
 		b, err = q.appendColumns(fmter, b)
 		if err != nil {
 			return nil, err
 		}
 	}
 
 	if q.hasTables() {
 		b, err = q.appendTables(fmter, b)
 		if err != nil {
 			return nil, err
 		}
 	}
 
 	if err := q.forEachInlineRelJoin(func(j *relationJoin) error {
 		b = append(b, ' ')
 		b, err = j.appendHasOneJoin(fmter, b, q)
 		return err
 	}); err != nil {
 		return nil, err
 	}
 
 	for _, j := range q.joins {
 		b, err = j.AppendQuery(fmter, b)
 		if err != nil {
 			return nil, err
 		}
 	}
 
 	b, err = q.appendIndexHints(fmter, b)
 	if err != nil {
 		return nil, err
 	}
 
 	b, err = q.appendWhere(fmter, b, true)
 	if err != nil {
 		return nil, err
 	}
 
 	if len(q.group) > 0 {
 		b = append(b, " GROUP BY "...)
 		for i, f := range q.group {
 			if i > 0 {
 				b = append(b, ", "...)
 			}
 			b, err = f.AppendQuery(fmter, b)
 			if err != nil {
 				return nil, err
 			}
 		}
 	}
 
 	if len(q.having) > 0 {
 		b = append(b, " HAVING "...)
 		for i, f := range q.having {
 			if i > 0 {
 				b = append(b, " AND "...)
 			}
 			b = append(b, '(')
 			b, err = f.AppendQuery(fmter, b)
 			if err != nil {
 				return nil, err
 			}
 			b = append(b, ')')
 		}
 	}
 
 	if !count {
 		b, err = q.appendOrder(fmter, b)
 		if err != nil {
 			return nil, err
 		}
 
 		if fmter.Dialect().Features().Has(feature.OffsetFetch) {
 			if q.limit > 0 && q.offset > 0 {
 				b = append(b, " OFFSET "...)
 				b = strconv.AppendInt(b, int64(q.offset), 10)
 				b = append(b, " ROWS"...)
 
 				b = append(b, " FETCH NEXT "...)
 				b = strconv.AppendInt(b, int64(q.limit), 10)
 				b = append(b, " ROWS ONLY"...)
 			} else if q.limit > 0 {
 				b = append(b, " OFFSET 0 ROWS"...)
 
 				b = append(b, " FETCH NEXT "...)
 				b = strconv.AppendInt(b, int64(q.limit), 10)
 				b = append(b, " ROWS ONLY"...)
 			} else if q.offset > 0 {
 				b = append(b, " OFFSET "...)
 				b = strconv.AppendInt(b, int64(q.offset), 10)
 				b = append(b, " ROWS"...)
 			}
 		} else {
 			if q.limit > 0 {
 				b = append(b, " LIMIT "...)
 				b = strconv.AppendInt(b, int64(q.limit), 10)
 			}
 			if q.offset > 0 {
 				b = append(b, " OFFSET "...)
 				b = strconv.AppendInt(b, int64(q.offset), 10)
 			}
 		}
 
 		if !q.selFor.IsZero() {
 			b = append(b, " FOR "...)
 			b, err = q.selFor.AppendQuery(fmter, b)
 			if err != nil {
 				return nil, err
 			}
 		}
 	}
 
 	if len(q.union) > 0 {
 		b = append(b, ')')
 
 		for _, u := range q.union {
 			b = append(b, u.expr...)
 			b = append(b, '(')
 			b, err = u.query.AppendQuery(fmter, b)
 			if err != nil {
 				return nil, err
 			}
 			b = append(b, ')')
 		}
 	}
 
 	if cteCount {
 		b = append(b, ") SELECT count(*) FROM _count_wrapper"...)
 	}
 
 	return b, nil
 }
 
 func (q *SelectQuery) appendColumns(fmter schema.Formatter, b []byte) (_ []byte, err error) {
 	start := len(b)
 
 	switch {
 	case q.columns != nil:
 		for i, col := range q.columns {
 			if i > 0 {
 				b = append(b, ", "...)
 			}
 
 			if col.Args == nil && q.table != nil {
 				if field, ok := q.table.FieldMap[col.Query]; ok {
 					b = append(b, q.table.SQLAlias...)
 					b = append(b, '.')
 					b = append(b, field.SQLName...)
 					continue
 				}
 			}
 
 			b, err = col.AppendQuery(fmter, b)
 			if err != nil {
 				return nil, err
 			}
 		}
 	case q.table != nil:
 		if len(q.table.Fields) > 10 && fmter.IsNop() {
 			b = append(b, q.table.SQLAlias...)
 			b = append(b, '.')
 			b = fmter.Dialect().AppendString(b, fmt.Sprintf("%d columns", len(q.table.Fields)))
 		} else {
 			b = appendColumns(b, q.table.SQLAlias, q.table.Fields)
 		}
 	default:
 		b = append(b, '*')
 	}
 
 	if err := q.forEachInlineRelJoin(func(join *relationJoin) error {
 		if len(b) != start {
 			b = append(b, ", "...)
 			start = len(b)
 		}
 
 		b, err = q.appendInlineRelColumns(fmter, b, join)
 		if err != nil {
 			return err
 		}
 
 		return nil
 	}); err != nil {
 		return nil, err
 	}
 
 	b = bytes.TrimSuffix(b, []byte(", "))
 
 	return b, nil
 }
 
 func (q *SelectQuery) appendInlineRelColumns(
 	fmter schema.Formatter, b []byte, join *relationJoin,
 ) (_ []byte, err error) {
 	join.applyTo(q)
 
 	if join.columns != nil {
 		table := join.JoinModel.Table()
 		for i, col := range join.columns {
 			if i > 0 {
 				b = append(b, ", "...)
 			}
 
 			if col.Args == nil {
 				if field, ok := table.FieldMap[col.Query]; ok {
 					b = join.appendAlias(fmter, b)
 					b = append(b, '.')
 					b = append(b, field.SQLName...)
 					b = append(b, " AS "...)
 					b = join.appendAliasColumn(fmter, b, field.Name)
 					continue
 				}
 			}
 
 			b, err = col.AppendQuery(fmter, b)
 			if err != nil {
 				return nil, err
 			}
 		}
 		return b, nil
 	}
 
 	for i, field := range join.JoinModel.Table().Fields {
 		if i > 0 {
 			b = append(b, ", "...)
 		}
 		b = join.appendAlias(fmter, b)
 		b = append(b, '.')
 		b = append(b, field.SQLName...)
 		b = append(b, " AS "...)
 		b = join.appendAliasColumn(fmter, b, field.Name)
 	}
 	return b, nil
 }
 
 func (q *SelectQuery) appendTables(fmter schema.Formatter, b []byte) (_ []byte, err error) {
 	b = append(b, " FROM "...)
 	return q.appendTablesWithAlias(fmter, b)
 }
 
 func (q *SelectQuery) appendOrder(fmter schema.Formatter, b []byte) (_ []byte, err error) {
 	if len(q.order) > 0 {
 		b = append(b, " ORDER BY "...)
 
 		for i, f := range q.order {
 			if i > 0 {
 				b = append(b, ", "...)
 			}
 			b, err = f.AppendQuery(fmter, b)
 			if err != nil {
 				return nil, err
 			}
 		}
 
 		return b, nil
 	}
 	return b, nil
 }
 
 //------------------------------------------------------------------------------
 
 func (q *SelectQuery) Rows(ctx context.Context) (*sql.Rows, error) {
 	if q.err != nil {
 		return nil, q.err
 	}
 
 	if err := q.beforeAppendModel(ctx, q); err != nil {
 		return nil, err
 	}
 
 	queryBytes, err := q.AppendQuery(q.db.fmter, q.db.makeQueryBytes())
 	if err != nil {
 		return nil, err
 	}
 
 	query := internal.String(queryBytes)
 	return q.conn.QueryContext(ctx, query)
 }
 
 func (q *SelectQuery) Exec(ctx context.Context, dest ...interface{}) (res sql.Result, err error) {
 	if q.err != nil {
 		return nil, q.err
 	}
 	if err := q.beforeAppendModel(ctx, q); err != nil {
 		return nil, err
 	}
 
 	queryBytes, err := q.AppendQuery(q.db.fmter, q.db.makeQueryBytes())
 	if err != nil {
 		return nil, err
 	}
 
 	query := internal.String(queryBytes)
 
 	if len(dest) > 0 {
 		model, err := q.getModel(dest)
 		if err != nil {
 			return nil, err
 		}
 
 		res, err = q.scan(ctx, q, query, model, true)
 		if err != nil {
 			return nil, err
 		}
 	} else {
 		res, err = q.exec(ctx, q, query)
 		if err != nil {
 			return nil, err
 		}
 	}
 
 	return res, nil
 }
 
 func (q *SelectQuery) Scan(ctx context.Context, dest ...interface{}) error {
 	if q.err != nil {
 		return q.err
 	}
 
 	model, err := q.getModel(dest)
 	if err != nil {
 		return err
 	}
 
 	if q.table != nil {
 		if err := q.beforeSelectHook(ctx); err != nil {
 			return err
 		}
 	}
 
 	if err := q.beforeAppendModel(ctx, q); err != nil {
 		return err
 	}
 
 	queryBytes, err := q.AppendQuery(q.db.fmter, q.db.makeQueryBytes())
 	if err != nil {
 		return err
 	}
 
 	query := internal.String(queryBytes)
 
 	res, err := q.scan(ctx, q, query, model, true)
 	if err != nil {
 		return err
 	}
 
 	if n, _ := res.RowsAffected(); n > 0 {
 		if tableModel, ok := model.(TableModel); ok {
 			if err := q.selectJoins(ctx, tableModel.getJoins()); err != nil {
 				return err
 			}
 		}
 	}
 
 	if q.table != nil {
 		if err := q.afterSelectHook(ctx); err != nil {
 			return err
 		}
 	}
 
 	return nil
 }
 
 func (q *SelectQuery) beforeSelectHook(ctx context.Context) error {
 	if hook, ok := q.table.ZeroIface.(BeforeSelectHook); ok {
 		if err := hook.BeforeSelect(ctx, q); err != nil {
 			return err
 		}
 	}
 	return nil
 }
 
 func (q *SelectQuery) afterSelectHook(ctx context.Context) error {
 	if hook, ok := q.table.ZeroIface.(AfterSelectHook); ok {
 		if err := hook.AfterSelect(ctx, q); err != nil {
 			return err
 		}
 	}
 	return nil
 }
 
 func (q *SelectQuery) Count(ctx context.Context) (int, error) {
 	if q.err != nil {
 		return 0, q.err
 	}
 
 	qq := countQuery{q}
 
 	queryBytes, err := qq.AppendQuery(q.db.fmter, nil)
 	if err != nil {
 		return 0, err
 	}
 
 	query := internal.String(queryBytes)
 	ctx, event := q.db.beforeQuery(ctx, qq, query, nil, query, q.model)
 
 	var num int
 	err = q.conn.QueryRowContext(ctx, query).Scan(&num)
 
 	q.db.afterQuery(ctx, event, nil, err)
 
 	return num, err
 }
 
 func (q *SelectQuery) ScanAndCount(ctx context.Context, dest ...interface{}) (int, error) {
 	if _, ok := q.conn.(*DB); ok {
 		return q.scanAndCountConc(ctx, dest...)
 	}
 	return q.scanAndCountSeq(ctx, dest...)
 }
 
 func (q *SelectQuery) scanAndCountConc(ctx context.Context, dest ...interface{}) (int, error) {
 	var count int
 	var wg sync.WaitGroup
 	var mu sync.Mutex
 	var firstErr error
 
 	if q.limit >= 0 {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
 
 			if err := q.Scan(ctx, dest...); err != nil {
 				mu.Lock()
 				if firstErr == nil {
 					firstErr = err
 				}
 				mu.Unlock()
 			}
 		}()
 	}
 
 	wg.Add(1)
 	go func() {
 		defer wg.Done()
 
 		var err error
 		count, err = q.Count(ctx)
 		if err != nil {
 			mu.Lock()
 			if firstErr == nil {
 				firstErr = err
 			}
 			mu.Unlock()
 		}
 	}()
 
 	wg.Wait()
 	return count, firstErr
 }
 
 func (q *SelectQuery) scanAndCountSeq(ctx context.Context, dest ...interface{}) (int, error) {
 	var firstErr error
 
 	if q.limit >= 0 {
 		firstErr = q.Scan(ctx, dest...)
 	}
 
 	count, err := q.Count(ctx)
 	if err != nil && firstErr == nil {
 		firstErr = err
 	}
 
 	return count, firstErr
 }
 
 func (q *SelectQuery) Exists(ctx context.Context) (bool, error) {
 	if q.err != nil {
 		return false, q.err
 	}
 
 	if q.hasFeature(feature.SelectExists) {
 		return q.selectExists(ctx)
 	}
 	return q.whereExists(ctx)
 }
 
 func (q *SelectQuery) selectExists(ctx context.Context) (bool, error) {
 	qq := selectExistsQuery{q}
 
 	queryBytes, err := qq.AppendQuery(q.db.fmter, nil)
 	if err != nil {
 		return false, err
 	}
 
 	query := internal.String(queryBytes)
 	ctx, event := q.db.beforeQuery(ctx, qq, query, nil, query, q.model)
 
 	var exists bool
 	err = q.conn.QueryRowContext(ctx, query).Scan(&exists)
 
 	q.db.afterQuery(ctx, event, nil, err)
 
 	return exists, err
 }
 
 func (q *SelectQuery) whereExists(ctx context.Context) (bool, error) {
 	qq := whereExistsQuery{q}
 
 	queryBytes, err := qq.AppendQuery(q.db.fmter, nil)
 	if err != nil {
 		return false, err
 	}
 
 	query := internal.String(queryBytes)
 	res, err := q.exec(ctx, qq, query)
 	if err != nil {
 		return false, err
 	}
 
 	n, err := res.RowsAffected()
 	if err != nil {
 		return false, err
 	}
 
 	return n == 1, nil
 }
 
 func (q *SelectQuery) String() string {
 	buf, err := q.AppendQuery(q.db.Formatter(), nil)
 	if err != nil {
 		panic(err)
 	}
 
 	return string(buf)
 }
 
 //------------------------------------------------------------------------------
 
 func (q *SelectQuery) QueryBuilder() QueryBuilder {
 	return &selectQueryBuilder{q}
 }
 
 func (q *SelectQuery) ApplyQueryBuilder(fn func(QueryBuilder) QueryBuilder) *SelectQuery {
 	return fn(q.QueryBuilder()).Unwrap().(*SelectQuery)
 }
 
 type selectQueryBuilder struct {
 	*SelectQuery
 }
 
 func (q *selectQueryBuilder) WhereGroup(
 	sep string, fn func(QueryBuilder) QueryBuilder,
 ) QueryBuilder {
 	q.SelectQuery = q.SelectQuery.WhereGroup(sep, func(qs *SelectQuery) *SelectQuery {
 		return fn(q).(*selectQueryBuilder).SelectQuery
 	})
 	return q
 }
 
 func (q *selectQueryBuilder) Where(query string, args ...interface{}) QueryBuilder {
 	q.SelectQuery.Where(query, args...)
 	return q
 }
 
 func (q *selectQueryBuilder) WhereOr(query string, args ...interface{}) QueryBuilder {
 	q.SelectQuery.WhereOr(query, args...)
 	return q
 }
 
 func (q *selectQueryBuilder) WhereDeleted() QueryBuilder {
 	q.SelectQuery.WhereDeleted()
 	return q
 }
 
 func (q *selectQueryBuilder) WhereAllWithDeleted() QueryBuilder {
 	q.SelectQuery.WhereAllWithDeleted()
 	return q
 }
 
 func (q *selectQueryBuilder) WherePK(cols ...string) QueryBuilder {
 	q.SelectQuery.WherePK(cols...)
 	return q
 }
 
 func (q *selectQueryBuilder) Unwrap() interface{} {
 	return q.SelectQuery
 }
 
 //------------------------------------------------------------------------------
 
 type joinQuery struct {
 	join schema.QueryWithArgs
 	on   []schema.QueryWithSep
 }
 
 func (j *joinQuery) AppendQuery(fmter schema.Formatter, b []byte) (_ []byte, err error) {
 	b = append(b, ' ')
 
 	b, err = j.join.AppendQuery(fmter, b)
 	if err != nil {
 		return nil, err
 	}
 
 	if len(j.on) > 0 {
 		b = append(b, " ON "...)
 		for i, on := range j.on {
 			if i > 0 {
 				b = append(b, on.Sep...)
 			}
 
 			b = append(b, '(')
 			b, err = on.AppendQuery(fmter, b)
 			if err != nil {
 				return nil, err
 			}
 			b = append(b, ')')
 		}
 	}
 
 	return b, nil
 }
 
 //------------------------------------------------------------------------------
 
 type countQuery struct {
 	*SelectQuery
 }
 
 func (q countQuery) AppendQuery(fmter schema.Formatter, b []byte) (_ []byte, err error) {
 	if q.err != nil {
 		return nil, q.err
 	}
 	return q.appendQuery(fmter, b, true)
 }
 
 //------------------------------------------------------------------------------
 
 type selectExistsQuery struct {
 	*SelectQuery
 }
 
 func (q selectExistsQuery) AppendQuery(fmter schema.Formatter, b []byte) (_ []byte, err error) {
 	if q.err != nil {
 		return nil, q.err
 	}
 
 	b = append(b, "SELECT EXISTS ("...)
 
 	b, err = q.appendQuery(fmter, b, false)
 	if err != nil {
 		return nil, err
 	}
 
 	b = append(b, ")"...)
 
 	return b, nil
 }
 
 //------------------------------------------------------------------------------
 
 type whereExistsQuery struct {
 	*SelectQuery
 }
 
 func (q whereExistsQuery) AppendQuery(fmter schema.Formatter, b []byte) (_ []byte, err error) {
 	if q.err != nil {
 		return nil, q.err
 	}
 
 	b = append(b, "SELECT 1 WHERE EXISTS ("...)
 
 	b, err = q.appendQuery(fmter, b, false)
 	if err != nil {
 		return nil, err
 	}
 
 	b = append(b, ")"...)
 
 	return b, nil
 }