Message type: E = Error
Message class:  DDLS - For DDL source handling 
Message number: 723
Message text: No DB systems were specified
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
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The SAP error message DDLS723: No DB systems were specified typically occurs when there is an issue with the database system configuration in the SAP environment. This error is often encountered during database-related operations, such as when trying to execute a Data Definition Language (DDL) statement or when performing database-related tasks in the SAP system.
Cause: Missing Database Configuration: The error may arise if the database systems are not properly configured in the SAP system. This could happen if the database connection settings are missing or incorrect. Incorrect Profile Settings: The instance profile or the database profile may not have the correct parameters set, leading to the system not recognizing the database. Transport Directory Issues: If you are working with transports, the transport directory may not be correctly set up, causing the system to not find the database systems. Authorization Issues: Lack of proper authorizations to access the database systems can also lead to this
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