How To Fix DT245 - DB length of the key of table & is too big (>&)

SAP Error Message - Details

• Message type: E = Error

• Message class: DT - Table activation (incl. indexes)

• Message number: 245

• Message text: DB length of the key of table & is too big (>&)

What causes this issue?

The sum of the DB field lengths of all key fields of the table is too
large.
The special features of the different database systems are used in the
calculation.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

You must either remove fields from the key or shorten the field lengths
of the key fields.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message DT245 - DB length of the key of table & is too big (>&) ?

  The SAP error message DT245 indicates that the length of the key for a specific database table exceeds the maximum allowed size. This typically occurs when the combined length of the key fields in a table exceeds the limit set by the database system or SAP itself.
  Cause:
  
  Key Length Exceeded: The primary cause of this error is that the total length of the key fields defined in the table exceeds the maximum limit. In SAP, the maximum length for a key is generally 255 bytes for a single key field, and the total length of all key fields combined should not exceed the database limit.
  Table Design: The design of the table may have too many key fields or the key fields may be defined with larger data types than necessary.
  Database Limitations: Different database systems (like Oracle, SQL Server, etc.) have their own limitations regarding key lengths.
  
  Solution:
  
  Review Table Definition: Check the definition of the table in the Data Dictionary (SE11). Look at the key fields and their data types.
  Reduce Key Length: If possible, reduce the number of key fields or change the data types of the key fields to smaller types (e.g., from CHAR to VARCHAR or from larger numeric types to smaller ones).
  Re-design the Table: If the table design is not optimal, consider redesigning the table to use a more efficient key structure. This might involve creating a surrogate key (like a numeric ID) that can serve as the primary key instead of using multiple fields.
  Consult Documentation: Refer to SAP documentation or the database documentation for specific limits and best practices regarding key lengths.
  Testing: After making changes, ensure to test the table thoroughly to confirm that the changes do not affect the application logic or data integrity.
  
  Related Information:
  
  Transaction Codes: Use SE11 to view and modify table definitions, and SE14 for database-related operations.
  Database-Specific Limits: Check the documentation for the specific database you are using with SAP to understand its limitations regarding key lengths.
  SAP Notes: Search for relevant SAP Notes that might provide additional insights or solutions related to this error message.
  
  If the issue persists after attempting the above solutions, it may be beneficial to consult with your SAP Basis team or reach out to SAP support for further assistance.