You can configure the deployment descriptor so that the EJB Container will perform a check during application start-up to see whether the O/R mapping in your persistent.xml is correct (that is, whether the abstract schema fits the database schema and whether the O/R mapping fulfills the O/R mapping rules).
We recommend that you enable O/R mapping verification. However, if you consider your O/R mapping correct and you want to achieve better performance at application start-up, you can switch off this option.
To enable the O/R mapping verification:
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1. Open persistent.xml → theGeneral tab.
2. Deselect the Switch off verification of database tables at deploy time option (if selected).
By default this option is deselected and the EJB Container checks the O/R mapping during the application start-up.
If you switch off the O/R mapping verification (that is, select the corresponding option in the NetWeaver Developer Studio), the system will add the <switch-off-verification> element in your persistent.xml.