Surrogate Key File Effective Practices

Here are a few thoughts on effectively working with IBM Infosphere, Information Server, DataStage surrogate key files, which may prove useful for developers.


  • The main thing about placement is that it be in a consistent location. Developers and production support teams should need to guess or look up where it is for every DataStage project. So, it is best to put the surrogate keys in same base path and that each project has its own subfolder to facilitate migrations and to reduce the possibility of human error. Here Is the patch structure, which is commonly use:


  • /data/SRKY/<<Project Name>>

Parameter Sets

  • As a best practice, the surrogate key file path should be in a parameter set and the parameter used in the jobs, as needed.  This simplifies maintenance, if and when changes to the path are required, and during migrations.

Surrogate Key Parameter Set Screenshot – Example Parameter Tab

Surrogate Key Parameter Set Screenshot – Example Values Tab

Surrogate Key Job Parameter Example Path using Parameter


  • DataStage must have permissions to:
    • The entire parent path
    • The project folder, and
    • The surrogate key files themselves.

To ensure the DataStage has access to the path and Surrogate files, ensure:

  • The ‘dsadm’ (owner) and ‘dstage’ (group) have access to folders in the path, with at least a “-rw-r–r–“ (644) permissions level. Keeping the permissions to a minimum can, for obvious reasons,  prevent inadvertent overwrites of the surrogate key files; thus, avoiding some, potentially, serious cleanup.
  • The ‘dsadm’ (owner) and ‘dstage’ (group) have access to the surrogate key files

Surrogate Key File Minimum Permissions