JDD/Data Sources

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JDD: Driver Locale | Handles | Data Sources | Data Driver | Error Messages | API: Connect Read Update Create Bulk Insert

A Data Source lists the DBMS database used or location of the data files.You need at least one Data Source to use JDD.

The examples here assume that you are using MySQL. You do not need to have installed MySQL at the client computer, but the client library is required.

Verb ddsrc returns the list of data sources given in the RDBMS. The result has 2 columns: the data source name, and a description of the driver:

   load 'data/ddmysql'
   db=: ''conew'jddmysql'
   ddsrc__db ch
|jdata             |MySQL|
|mysql             |MySQL|

The result will depend on the drivers you have set up. You should see an entry for jdata, which is the data source name you assigned to the jdata database.

Unlike J/ODBC,

  • you have to first connect to RDBMS server before making a ddsrc call.
  • a connection handle should be provided as the argument.
  • the driver description column is always the same for a given JDD driver.