Golang DB.Select方法代码示例

// SelectMissingIds accepts a table name as an input and a list of ids as a source.
// It returns a new list of ids that does not exist in the destination table
//
// 	* tblName : a table name
// 	* srcIds : a source ids
// 	* db : a pointer to connected databased
// 	* Returns a new list of ids which are not from the specified table
//
// The format of sql statement is:
// 	WITH dna (id) AS (VALUES (5),(6),(7),(8),(9))
// 	SELECT id FROM dna WHERE NOT EXISTS
// 	(SELECT 1 from ziartists WHERE id=dna.id)
func SelectMissingIds(tblName dna.String, srcIds *dna.IntArray, db *sqlpg.DB) (*dna.IntArray, error) {

	if srcIds.Length() > 0 {

		val := dna.StringArray(srcIds.Map(func(val dna.Int, idx dna.Int) dna.String {
			return "(" + val.ToString() + ")"
		}).([]dna.String))
		selectStmt := "with dna (id) as (values " + val.Join(",") + ") \n"
		selectStmt += "SELECT id FROM dna WHERE NOT EXISTS\n (SELECT 1 from " + tblName + "  WHERE id=dna.id)"
		ids := &[]dna.Int{}
		err := db.Select(ids, selectStmt)
		switch {
		case err != nil:
			return nil, err
		case err == nil && ids != nil:
			slice := dna.IntArray(*ids)
			return &slice, nil
		case err == nil && ids == nil:
			return &dna.IntArray{}, nil
		default:
			panic("Default case triggered. Case is not expected. Cannot select non existed ids")
		}
	} else {
		return nil, errors.New("Empty input array")
	}

}

// SelectMissingKeys accepts a table name as an input and a list of keys as a source.
// It returns a new list of keys that does not exist in the destination table
//
// 	* tblName : a table name
// 	* srcKeys : a source keys
// 	* db : a pointer to connected databased
// 	* Returns a new list of keys which are not from the specified table
//
// Notice: Only applied to a table having a column named "key".
// The column has to be indexed to ensure good performance
//
// The format of sql statement is:
//	with dna (key) as (values ('43f3HhhU6DGV'),('uFfgQhKbwAfN'),('RvFDlckJB5QU'),('uIF7rwd5wo4p'),('Kveukbhre1ry'),('oJ1lzAlKwJX6'),('43f3HhhU6DGV'),('uFfgQhKbwAfN'),('hfhtyMdywMau'),('PpZuccjYqy1b'))
//	select key from dna where key not in
//	(select key from nctalbums where key in ('43f3HhhU6DGV','uFfgQhKbwAfN','RvFDlckJB5QU','uIF7rwd5wo4p','Kveukbhre1ry','oJ1lzAlKwJX6','43f3HhhU6DGV','uFfgQhKbwAfN','hfhtyMdywMau','PpZuccjYqy1b'))
func SelectMissingKeys(tblName dna.String, srcKeys *dna.StringArray, db *sqlpg.DB) (*dna.StringArray, error) {
	if srcKeys.Length() > 0 {
		val := dna.StringArray(srcKeys.Map(func(val dna.String, idx dna.Int) dna.String {
			return `('` + val + `')`
		}).([]dna.String))
		val1 := dna.StringArray(srcKeys.Map(func(val dna.String, idx dna.Int) dna.String {
			return `'` + val + `'`
		}).([]dna.String))
		selectStmt := "with dna (key) as (values " + val.Join(",") + ") \n"
		selectStmt += "select key from dna where key not in \n(select key from " + tblName + " where key in (" + val1.Join(",") + "))"
		keys := &[]dna.String{}
		err := db.Select(keys, selectStmt)
		switch {
		case err != nil:
			return nil, err
		case err == nil && keys != nil:
			slice := dna.StringArray(*keys)
			return &slice, nil
		case err == nil && keys == nil:
			return &dna.StringArray{}, nil
		default:
			panic("Default case triggered. Case is not expected. Cannot select non existed keys")
		}
	} else {
		return nil, errors.New("Empty input array")
	}
}

// GetLastedChecktime returns a map which maps site to lasted checktime.
// Ex: "nssongs" => 2014-03-17 12:09:37
func GetLastedChecktime(db *sqlpg.DB) (map[dna.String]time.Time, error) {
	siteCts := &[]site_checktime{}
	ret := make(map[dna.String]time.Time)
	err := db.Select(siteCts, "select * from get_lasted_checktime();")
	if err == nil {
		for _, sitect := range *siteCts {
			ret[sitect.Site] = sitect.Checktime
			// dna.Log(sitect.Site, sitect.Checktime.Format(utils.DefaultTimeLayout))

		}
		return ret, nil
	} else {
		return nil, err
	}
}

// GetMoviesCurrentEps returns a map of MovideId and CurrentEps
// if CurrentEps is less than MaxEp.
// it returns an error if available.
//
// This function is used when we need to find all possible movie ids
// to update.
func GetMoviesCurrentEps(db *sqlpg.DB, tblName dna.String) (map[dna.Int]dna.Int, error) {
	var movieCurrentEps = make(map[dna.Int]dna.Int)
	ids := &[]dna.Int{}
	currentEps := &[]dna.Int{}
	err := db.Select(ids, dna.Sprintf(`SELECT id from %v where current_eps < max_ep order by id DESC`, tblName))
	if err != nil {
		return nil, err
	}
	err = db.Select(currentEps, dna.Sprintf(`SELECT current_eps from %v where current_eps < max_ep order by id DESC`, tblName))
	if err != nil {
		return nil, err
	}
	if len(*currentEps) != len(*ids) {
		return nil, errors.New("Length of IDs and CurrentEps is not correspondent")
	}
	for idx, movieid := range *ids {
		movieCurrentEps[movieid] = (*currentEps)[idx]
	}
	return movieCurrentEps, nil
}

func (alca *AlbumCategory) Save(db *sqlpg.DB) error {

	var last error
	var aids = dna.IntArray{}
	albums := &[]Album{}
	for _, album := range *(alca.Albums) {
		aids.Push(album.Id)
		// dna.Log(album)
	}
	query := "SELECT id, topics, genres from nsalbums WHERE id IN (" + aids.Join(",") + ")"
	// dna.Log(query)
	err := db.Select(albums, query)
	if err != nil {
		dna.Log(query, alca, *alca.Albums)
		dna.PanicError(err)
	}

	for _, album := range *(alca.Albums) {
		foundIndex := 0
		for j, anotherAlbum := range *(albums) {
			if album.Id == anotherAlbum.Id {
				foundIndex = j
			}
		}
		if foundIndex < len(*albums) {
			cat := album.Category.Concat((*albums)[foundIndex].Topics).Concat((*albums)[foundIndex].Genres).Unique()
			album.Category = cat.Filter(func(v dna.String, i dna.Int) dna.Bool {
				if v != "" {
					return true
				} else {
					return false
				}
			})

		}
		last = db.Update(album, "id", "category")

	}

	return last
}

// SelectNewSidsFromAlbums returns a slice  of songids from a table since the last specified time.
// The table has to be album type and has a column called songids.
func SelectNewSidsFromAlbums(tblName dna.String, lastTime time.Time, db *sqlpg.DB) *dna.IntArray {
	idsArrays := &[]dna.IntArray{}
	year := dna.Sprintf("%v", lastTime.Year())
	month := dna.Sprintf("%d", lastTime.Month())
	day := dna.Sprintf("%v", lastTime.Day())
	checktime := dna.Sprintf("'%v-%v-%v'", year, month, day)
	query := dna.Sprintf("SELECT songids FROM %s WHERE checktime >= %s", tblName, checktime)
	// dna.Log(query)
	err := db.Select(idsArrays, query)
	dna.PanicError(err)
	ids := &dna.IntArray{}
	if idsArrays != nil {
		for _, val := range *idsArrays {
			for _, id := range val {
				ids.Push(id)
			}
		}
		return ids
	} else {
		return nil
	}

}

// SelectMissingIds accepts a table name as an input and a range as a source.
// It returns a new list of ids that does not exist in the destination table
//
// 	* tblName : a table name
// 	* head, tail : first and last number defines a range
// 	* db : a pointer to connected databased
// 	* Returns a new list of ids which are not from the specified table
//
// The format of sql statement is:
// 	SELECT id FROM generate_series(5,9) id
// 	WHERE NOT EXISTS (SELECT 1 from ziartists where id = id.id)
func SelectMissingIdsWithRange(tblName dna.String, head, tail dna.Int, db *sqlpg.DB) (*dna.IntArray, error) {

	if head > tail {
		panic("Cannot create range: head has to be less than tail")
	}

	selectStmt := dna.Sprintf("SELECT id FROM generate_series(%v,%v) id \n", head, tail)
	selectStmt += "WHERE NOT EXISTS (SELECT 1 from " + tblName + " where id = id.id)"
	ids := &[]dna.Int{}
	err := db.Select(ids, selectStmt)
	switch {
	case err != nil:
		return nil, err
	case err == nil && ids != nil:
		slice := dna.IntArray(*ids)
		return &slice, nil
	case err == nil && ids == nil:
		return &dna.IntArray{}, nil
	default:
		panic("Default case triggered. Case is not expected. Cannot select non existed ids")
	}

}

// updateEmptyTitles returns an error if there is no missing titles
// of songs or videos.
func updateEmptyTitles(db *sqlpg.DB, siteConf *SiteConfig, lastId dna.Int) bool {
	var queryPat dna.String = "select id from %v where id > %v and title = ''"

	songids := &[]dna.Int{}
	songQuery := dna.Sprintf(queryPat, "csnsongs", lastId)
	db.Select(songids, songQuery)

	videoQuery := dna.Sprintf(queryPat, "csnvideos", lastId)
	videoids := &[]dna.Int{}
	db.Select(videoids, videoQuery)

	ids := dna.IntArray(*songids).Concat(dna.IntArray(*videoids))
	if ids.Length() > 0 {
		dna.Log(ids)
		state := NewStateHandlerWithExtSlice(new(csn.SongVideoUpdater), &ids, siteConf, db)
		Update(state)
		RecoverErrorQueries(SqlErrorLogPath, db)
		return false
	} else {
		// dna.Log("No record needs to be updated.")
		return true
	}
	// return donec
}