Understand data change frequency

Data change frequencies are not processed by the MES middleware maintenance service. These frequencies generate samples with the corresponding event through the middleware. In general, these are MES Operations type transactions that generates a new sample for an entity when the call is processed by the middleware.

• Job Start/Job End

  Both these frequencies are based on a job running on an entity. When a QM specification has the context of an item (or item category) and/or operation, then a job must be active on the entity for the QM specification to be active.

  • If the QM specification has a sample plan that contains a job start frequency, the job start transaction generates a new sample on the entity.

  • If the QM specification has a sample plan that contains a job end frequency, the job end transaction generates a new sample on the entity.

• Lot number of main item produced changes

  This frequency is based on a job running on an entity. When the call is made to change the lot number of the main item produced (JobExec.SetCurLotData API call for BOM Position 0 which is the main item produced), a new sample is generated on the entity. This event happens when the lot number is set for the job, not when the job produce transaction is called. The lot number produced is different from the previous lot number.

  This event frequency is applicable only to QM specifications that have item/item category and/or process/operation contexts. A QM specification with only an entity context will not have samples generated for this frequency type.

• Manual

  This frequency definition is provided as a mechanism to indicate that the Sample.GenerateSample API call will be used at run time to generate an ad-hoc sample. It is not associated to any other MES Operations or performance transaction. Since a QM specification must include a sample plan and a sample plan must include a sample plan frequency, the manual frequency is provided so that a manual QM specification can be defined in the system and used by the call.