SAP S/4HANA Error 263: Invalid SQL Alias

Analyze the error message and surrounding code. The error often occurs in custom reports, interfaces, or enhancements that directly interact with the database using SQL or Open SQL.

Review SQL statements for invalid alias definitions. Common issues include: using reserved keywords as aliases, special characters, excessively long aliases, or aliases that are not properly quoted when necessary.

SELECT T1.field1 AS invalid-alias FROM table1 AS T1;

Apply valid alias naming conventions. Aliases should typically start with an alphabet character, contain only alphanumeric characters and underscores, and not exceed the maximum length allowed by the database system.

SELECT T1.field1 AS valid_alias FROM table1 AS T1;

If the alias is a reserved keyword or contains special characters, enclose it in double quotes (for SQL) or backticks (for some SQL dialects, though double quotes are standard SQL). However, it's best practice to avoid such aliases altogether.

SELECT T1.field1 AS "SELECT" FROM table1 AS T1; -- Avoid if possible

If the error occurs within an ABAP program using Open SQL, the syntax for aliases is generally more flexible, but still adheres to certain rules. Consult SAP Notes for specific Open SQL alias limitations.

SELECT field1 AS invalid_alias FROM table1.

Test the corrected code thoroughly in a non-production environment before deploying to production.

Identify the exact SAP object (transaction code, program name, etc.) that triggers the error. This is crucial for pinpointing the source.

Use transaction SE80 or SE38 to examine the ABAP code of the identified object. Look for any SQL statements, especially those involving table joins or derived tables, where aliases are defined.

If an invalid alias is found in standard SAP code, it's likely a bug. Search the SAP Support Portal (SAP Notes) for known issues related to the error code and the specific transaction or program. If a relevant SAP Note exists, follow its instructions for correction (e.g., applying a correction transport).

If no SAP Note is found, consider opening an incident with SAP Support, providing detailed information about the error, the affected object, and steps to reproduce it.

Avoid directly modifying SAP standard code unless explicitly instructed by an SAP Note or SAP Support. Unauthorized modifications can lead to significant issues during future upgrades or support activities.

Identify the database user that the SAP application server uses to connect to the HANA database. This is typically configured in the SAP system's database connection parameters (e.g., DBCONNECT).

Log in to the SAP HANA database using a suitable tool (e.g., SAP HANA Studio, hdbsql) with the identified database user credentials.

Execute a simple SQL query to check for basic syntax errors or permission issues. While this error is specific to aliases, a broader check can sometimes reveal underlying connectivity or permission problems that manifest indirectly.

SELECT 'Hello World' FROM DUMMY;

Review the privileges granted to the database user. Ensure they have sufficient permissions to execute the SQL statements that are causing the error. While not directly related to alias syntax, insufficient privileges can sometimes lead to unexpected SQL behavior.

Check the SAP application server's system logs (SM21) and the HANA database trace files for any connection errors or unusual activity that might coincide with the occurrence of error 263.