Reference Guide
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SQL Proxy
Single Sign-On Settings for Or...
The second password definition is required to provide authentication to the SQL Proxy when using SSO. In the Portal Functions screen, the Second Password Enabled function should be assigned to the user group that will use the SQL Proxy SSO feature. To activate the second password use:
After enabling the second password for a user group, the users in that group can assign their second passwords to their own accounts in the Account Settings screen.
If SSO is not supported for the target databases in SQL Proxy, the target database Username and Password must be used as the connection user. The Second password definition should not be defined for the connection user