Function getIndices

backend/plugin/db/sqlite/sync.go:169–224

getIndices gets all indices of a database.

(txn *sql.Tx)

// getIndices gets all indices of a database.
func getIndices(txn *sql.Tx) (map[string][]*storepb.IndexMetadata, error) {
	indexMap := make(map[string][]*storepb.IndexMetadata)
	query := `
		SELECT
			tbl_name, name, sql
		FROM sqlite_schema
		WHERE type ='index' AND name NOT LIKE 'sqlite_%'
		ORDER BY tbl_name, name;`
	rows, err := txn.Query(query)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	for rows.Next() {
		var tableName, statement string
		index := &storepb.IndexMetadata{}
		if err := rows.Scan(&tableName, &index.Name, &statement); err != nil {
			return nil, err
		}
		index.Unique = strings.Contains(statement, " UNIQUE INDEX ")
		indexMap[tableName] = append(indexMap[tableName], index)
	}
	if err := rows.Err(); err != nil {
		return nil, util.FormatErrorWithQuery(err, query)
	}

	for _, indexes := range indexMap {
		for _, index := range indexes {
			if err := func() error {
				query := fmt.Sprintf("pragma index_info(%s);", index.Name)
				rows, err := txn.Query(query)
				if err != nil {
					return err
				}
				defer rows.Close()
				for rows.Next() {
					var unusedPosition int
					var unusedCid, expression string
					if err := rows.Scan(&unusedPosition, &unusedCid, &expression); err != nil {
						return err
					}
					index.Expressions = append(index.Expressions, expression)
				}
				if err := rows.Err(); err != nil {
					return util.FormatErrorWithQuery(err, query)
				}
				return nil
			}(); err != nil {
				return nil, err
			}
		}
	}

	return indexMap, nil
}

func getViews(txn *sql.Tx) ([]*storepb.ViewMetadata, error) {