Documentation Home
Connectors and APIs Manual
Download this Manual
PDF (US Ltr) - 4.1Mb
PDF (A4) - 4.1Mb


3.5.3.10 BLOB/CLOB processing

  • blobSendChunkSize

    Chunk size to use when sending BLOB/CLOBs via server-prepared statements. Note that this value cannot exceed the value of 'maxAllowedPacket' and, if that is the case, then this value will be corrected automatically.

    Default Value 1048576
    Since Version 3.1.9
  • blobsAreStrings

    Should the driver always treat BLOBs as Strings - specifically to work around dubious metadata returned by the server for GROUP BY clauses?

    Default Value false
    Since Version 5.0.8
  • clobCharacterEncoding

    The character encoding to use for sending and retrieving TEXT, MEDIUMTEXT and LONGTEXT values instead of the configured connection 'characterEncoding'.

    Since Version 5.0.0
  • emulateLocators

    Should the driver emulate 'java.sql.Blob' with locators? With this feature enabled, the driver will delay loading the actual Blob data until the one of the retrieval methods ('getInputStream()', 'getBytes()', and so forth) on the blob data stream has been accessed. For this to work, you must use a column alias with the value of the column to the actual name of the Blob. The feature also has the following restrictions: The SELECT that created the result set must reference only one table, the table must have a primary key; the SELECT must alias the original blob column name, specified as a string, to an alternate name; the SELECT must cover all columns that make up the primary key.

    Default Value false
    Since Version 3.1.0
  • functionsNeverReturnBlobs

    Should the driver always treat data from functions returning BLOBs as Strings - specifically to work around dubious metadata returned by the server for "GROUP BY" clauses?

    Default Value false
    Since Version 5.0.8
  • locatorFetchBufferSize

    If 'emulateLocators' is configured to "true", what size buffer should be used when fetching BLOB data for 'getBinaryInputStream()'?

    Default Value 1048576
    Since Version 3.2.1