Method SetLatestVersion

internal/database/postgres.go:910–936

SetLatestVersion sets is_latest=true on the given version and false on all other versions of the same server. Passing an empty version clears is_latest for all rows. The clear and set are issued as separate statements because the unique partial index idx_unique_latest_per_server is non-deferrable a

(ctx context.Context, tx pgx.Tx, serverName, version string)

// idx_unique_latest_per_server is non-deferrable and Postgres checks it row-by-row within
// a single UPDATE, which would trip when flipping one row's flag off and another's on.
func (db *PostgreSQL) SetLatestVersion(ctx context.Context, tx pgx.Tx, serverName, version string) error {
	if ctx.Err() != nil {
		return ctx.Err()
	}

	executor := db.getExecutor(tx)

	if _, err := executor.Exec(ctx,
		`UPDATE servers SET is_latest = false WHERE server_name = $1 AND is_latest = true AND version <> $2`,
		serverName, version,
	); err != nil {
		return fmt.Errorf("failed to clear previous latest version: %w", err)
	}

	if version == "" {
		return nil
	}

	if _, err := executor.Exec(ctx,
		`UPDATE servers SET is_latest = true WHERE server_name = $1 AND version = $2 AND is_latest = false`,
		serverName, version,
	); err != nil {
		return fmt.Errorf("failed to set latest version: %w", err)
	}

	return nil
}

// Close closes the database connection
func (db *PostgreSQL) Close() error {