Package org.mariadb.jdbc.client.result

Class StreamingResult

  • All Implemented Interfaces:
    AutoCloseable, ResultSet, Wrapper, org.mariadb.jdbc.client.Completion, org.mariadb.jdbc.message.ServerMessage
    public class StreamingResult
extends Result
    Streaming result-set implementation. Implementation rely on reading as many rows than fetch size required, keeping remaining rows in TCP-IP buffer

    The server usually expects clients to read off the result set relatively quickly. The net_write_timeout server variable controls this behavior (defaults to 60s).

    If you don't expect results to be handled in this amount of time there is a different possibility:

    • With >= MariaDB server, you can use the query "SET STATEMENT net_write_timeout=10000 FOR XXX" with XXX your "normal" query. This will indicate that specifically for this query, net_write_timeout will be set to a longer time (10000 in this example).
    • for non mariadb servers, a specific query will have to temporarily set net_write_timeout ("SET STATEMENT net_write_timeout=..."), and set it back afterward.
    • if your application usually uses a lot of long queries with fetch size, the connection can be set using option "sessionVariables=net_write_timeout=xxx"

    Even using setFetchSize, the server will send all results to the client.

    If another query is executed on the same connection when a streaming result-set has not been fully read, the connector will put the whole remaining streaming result-set in memory in order to execute the next query. This can lead to OutOfMemoryError if not handled.