[bug] Query Select uses wrong table name when ModelTableExpr is called

[mingoal]

bun@v1.1.17

When ModelTableExpr is called, query select constructs wrong SQL statement.

db.NewSelect().
    Model(&AliasTableName{}).
    ModelTableExpr("model_table_expr_name").
    Where("id = ?", id).
    Scan(context.Background())

The result will be

select alias_table_name.id from model_table_expr_name where ...

The root cause is query_select.go:(*SelectQuery).appendColumns doesn't check baseQuery.modelTableName, uses table alias directly.

The following code fixes this bug, for your reference.

func (q *SelectQuery) appendColumns(fmter schema.Formatter, b []byte) (_ []byte, err error) {
	start := len(b)

	tableName := q.table.SQLAlias
	if !q.baseQuery.modelTableName.IsZero() {
		tableName = schema.Safe(q.baseQuery.modelTableName.Query)
	}

	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, tableName...)
					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, tableName...)
			b = append(b, '.')
			b = fmter.Dialect().AppendString(b, fmt.Sprintf("%d columns", len(q.table.Fields)))
		} else {
			b = appendColumns(b, tableName, 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
}

[vmihailenco]

You're supposed to include the alias in the expr: ModelTableExpr("model_table_expr_name AS table_alias"). Because of this, your code will fail when the alias is present.

[mingoal]

You're supposed to include the alias in the expr: ModelTableExpr("model_table_expr_name AS table_alias"). Because of this, your code will fail when the alias is present.

But insert/update don't require to do it. I suppose select would align with other operations.

If this is a must action, it closed the door to use one model for several tables have different table name.