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package sqlite3
import (
"context"
"database/sql"
"github.com/matrix-org/dendrite/common"
"github.com/matrix-org/dendrite/syncapi/types"
)
const streamIDTableSchema = `
-- Global stream ID counter, used by other tables.
CREATE TABLE IF NOT EXISTS syncapi_stream_id (
stream_name TEXT NOT NULL PRIMARY KEY,
stream_id INT DEFAULT 0,
UNIQUE(stream_name)
);
INSERT INTO syncapi_stream_id (stream_name, stream_id) VALUES ("global", 0)
ON CONFLICT DO NOTHING;
`
const increaseStreamIDStmt = "" +
"UPDATE syncapi_stream_id SET stream_id = stream_id + 1 WHERE stream_name = $1"
const selectStreamIDStmt = "" +
"SELECT stream_id FROM syncapi_stream_id WHERE stream_name = $1"
type streamIDStatements struct {
increaseStreamIDStmt *sql.Stmt
selectStreamIDStmt *sql.Stmt
}
func (s *streamIDStatements) prepare(db *sql.DB) (err error) {
_, err = db.Exec(streamIDTableSchema)
if err != nil {
return
}
if s.increaseStreamIDStmt, err = db.Prepare(increaseStreamIDStmt); err != nil {
return
}
if s.selectStreamIDStmt, err = db.Prepare(selectStreamIDStmt); err != nil {
return
}
return
}
func (s *streamIDStatements) nextStreamID(ctx context.Context, txn *sql.Tx) (pos types.StreamPosition, err error) {
increaseStmt := common.TxStmt(txn, s.increaseStreamIDStmt)
selectStmt := common.TxStmt(txn, s.selectStreamIDStmt)
if _, err = increaseStmt.ExecContext(ctx, "global"); err != nil {
return
}
if err = selectStmt.QueryRowContext(ctx, "global").Scan(&pos); err != nil {
return
}
return
}
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