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3.5.3.14 Debugging/Profiling

  • logger

    The name of a class that implements 'com.mysql.cj.log.Log' that will be used to log messages to. (default is 'com.mysql.cj.log.StandardLogger', which logs to STDERR).

    Default Value com.mysql.cj.log.StandardLogger
    Since Version 3.1.1
  • profilerEventHandler

    Name of a class that implements the interface 'com.mysql.cj.log.ProfilerEventHandler' that will be used to handle profiling/tracing events.

    Default Value com.mysql.cj.log.LoggingProfilerEventHandler
    Since Version 5.1.6
  • useNanosForElapsedTime

    For profiling/debugging functionality that measures elapsed time, should the driver try to use nanoseconds resolution?

    Default Value false
    Since Version 5.0.7
  • maxQuerySizeToLog

    Controls the maximum length of the part of a query that will get logged when profiling or tracing.

    Default Value 2048
    Since Version 3.1.3
  • maxByteArrayAsHex

    Maximum size for a byte array parameter in a prepared statement that is converted to a hexadecimal literal when interpolated by 'JdbcPreparedStatement.toString()'. Any byte arrays larger than this value are interpolated generically as "** BYTE ARRAY DATA **".

    Default Value 1024
    Since Version 8.0.31
  • profileSQL

    Trace queries and their execution/fetch times to the configured 'profilerEventHandler'.

    Default Value false
    Since Version 3.1.0
  • logSlowQueries

    Should queries that take longer than 'slowQueryThresholdMillis' or detected by the 'autoSlowLog' monitoring be reported to the registered 'profilerEventHandler'?

    Default Value false
    Since Version 3.1.2
  • slowQueryThresholdMillis

    If 'logSlowQueries' is enabled, how long, in milliseconds, should a query take before it is logged as slow?

    Default Value 2000
    Since Version 3.1.2
  • slowQueryThresholdNanos

    If 'logSlowQueries' is enabled, 'useNanosForElapsedTime' is set to "true", and this property is set to a non-zero value, the driver will use this threshold, in nanosecond units, to determine if a query was slow.

    Default Value 0
    Since Version 5.0.7
  • autoSlowLog

    Instead of using 'slowQueryThreshold*' to determine if a query is slow enough to be logged, maintain statistics that allow the driver to determine queries that are outside the 99th percentile?

    Default Value true
    Since Version 5.1.4
  • explainSlowQueries

    If 'logSlowQueries' is enabled, should the driver automatically issue an 'EXPLAIN' on the server and send the results to the configured logger at a WARN level?

    Default Value false
    Since Version 3.1.2
  • gatherPerfMetrics

    Should the driver gather performance metrics, and report them via the configured logger every 'reportMetricsIntervalMillis' milliseconds?

    Default Value false
    Since Version 3.1.2
  • reportMetricsIntervalMillis

    If 'gatherPerfMetrics' is enabled, how often should they be logged (in milliseconds)?

    Default Value 30000
    Since Version 3.1.2
  • logXaCommands

    Should the driver log XA commands sent by 'MysqlXaConnection' to the server, at the DEBUG level of logging?

    Default Value false
    Since Version 5.0.5
  • traceProtocol

    Should the network protocol be logged at the TRACE level?

    Default Value false
    Since Version 3.1.2
  • enablePacketDebug

    When enabled, a ring-buffer of 'packetDebugBufferSize' packets will be kept, and dumped when exceptions are thrown in key areas in the driver's code.

    Default Value false
    Since Version 3.1.3
  • packetDebugBufferSize

    The maximum number of packets to retain when 'enablePacketDebug' is "true".

    Default Value 20
    Since Version 3.1.3
  • useUsageAdvisor

    Should the driver issue usage warnings advising proper and efficient usage of JDBC and MySQL Connector/J to the 'profilerEventHandler'?

    Default Value false
    Since Version 3.1.1
  • resultSetSizeThreshold

    If 'useUsageAdvisor' is "true", how many rows should a result set contain before the driver warns that it is suspiciously large?

    Default Value 100
    Since Version 5.0.5
  • autoGenerateTestcaseScript

    Should the driver dump the SQL it is executing, including server-side prepared statements to STDERR?

    Default Value false
    Since Version 3.1.9