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Description

This error indicates that a column name is used more than once within the same context in a SQLScript statement, view, or procedure definition. It commonly arises during the creation or modification of database objects in SAP HANA when the system detects an ambiguity.

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Error Message

ERR_SQLSCRIPT_BUILTIN_DUPLICATE_COLUMN_NAME

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Known Causes

4 known causes

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Identical Column Names in Definition

This occurs when two or more columns within a single SQLScript statement, view, or procedure definition are assigned the exact same name, making them indistinguishable.

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Wildcard Selection with Calculated Columns

When a 'SELECT *' statement is combined with explicitly defined calculated columns that happen to have names matching existing table columns, this conflict can arise.

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Join Operations Creating Duplicates

Joining tables that have identically named columns without properly aliasing them can lead to this error when the joined result set attempts to output both columns.

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Duplicate Names in Subqueries/Derived Tables

Subqueries or derived tables that project columns with names already present in the outer query's scope can trigger this error.

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Solutions

3 solutions available

1. Identify and Rename Duplicate Columns in SQLScript medium

Locate and rename columns that share the same name within a SQLScript procedure or function.

1

Analyze the SQLScript code that is causing the error. This often occurs in SELECT statements, JOINs, or within table expressions.

Review the SQLScript code for the specific procedure or function throwing error 1329.

2

Look for instances where multiple columns are selected or generated with identical names. This can happen when joining tables that have columns with the same name and they are not aliased differently, or when using subqueries that produce duplicate column names.

Example of problematic code:

sql
SELECT
    t1.id, t1.name, t2.id
FROM
    table1 t1
JOIN
    table2 t2 ON t1.id = t2.fk_id;


In this example, both `t1.id` and `t2.id` will lead to a duplicate column name error if not aliased.

3

Rename one or more of the duplicate columns using aliases. This is the most common and direct solution.

Corrected code:

sql
SELECT
    t1.id AS table1_id, t1.name, t2.id AS table2_id
FROM
    table1 t1
JOIN
    table2 t2 ON t1.id = t2.fk_id;

4

If the duplicates arise from subqueries or derived tables, ensure that all columns within those constructs are uniquely named or aliased.

Example with subquery:

sql
SELECT
    a.col1, b.col1
FROM
    (SELECT id, data FROM source1) AS a
JOIN
    (SELECT id, value FROM source2) AS b ON a.id = b.id;


This will cause an error. Corrected:

sql
SELECT
    a.id AS source1_id, a.data, b.value
FROM
    (SELECT id, data FROM source1) AS a
JOIN
    (SELECT id, value FROM source2) AS b ON a.id = b.id;

2. Resolve Implicit Column Naming Conflicts in Derived Tables medium

Address duplicate column names that occur implicitly when creating derived tables or common table expressions (CTEs) without explicit aliasing.

1

Examine any `WITH` clauses (CTEs) or subqueries used as derived tables in your SQLScript. Pay close attention to the column names being projected from the inner queries.

Consider a CTE like this:

sql
WITH temp_data AS (
    SELECT
        order_id, product_id
    FROM
        sales_orders
)
SELECT
    order_id, product_id
FROM
    temp_data;

2

If the CTE or derived table itself is selecting columns that are later referenced and could conflict, or if multiple CTEs are used and their projected columns have the same names, you need to alias them.

Example of conflict within CTE and outer query:

sql
WITH order_details AS (
    SELECT
        order_id, order_date
    FROM
        orders
)
SELECT
    order_id, order_date
FROM
    order_details;


If `order_id` or `order_date` are also selected directly in the outer query from another source, this can cause issues.

3

Ensure that all columns selected within a CTE or derived table are uniquely named or explicitly aliased to avoid conflicts with other columns in the same scope or in the outer query.

Corrected CTE usage:

sql
WITH order_details AS (
    SELECT
        order_id AS order_ref, order_date
    FROM
        orders
)
SELECT
    od.order_ref, od.order_date
FROM
    order_details od;

3. Review Stored Procedure/Function Signatures and Return Values medium

Ensure that parameters and return values in SQLScript procedures and functions do not introduce duplicate column names.

1

If the error occurs within a stored procedure or function definition, examine its `CREATE PROCEDURE` or `CREATE FUNCTION` statement. Check both input parameters and the structure of the return table or scalar value.

Review the `CREATE PROCEDURE` or `CREATE FUNCTION` statement.

2

Verify that no input parameter has the same name as a column being selected or generated within the procedure/function body. Also, ensure that the columns in the return table definition or the structure of the returned scalar value are unique.

Example of a problematic function signature and body:

sql
CREATE FUNCTION get_user_data (user_id INT)
RETURNS TABLE (user_id INT, name VARCHAR(100))
AS
BEGIN
    -- Assume a source table also has 'user_id' and 'name'
    RETURN SELECT user_id, name FROM users WHERE id = :user_id;
END;


If the `users` table also has `user_id` and `name` columns, and these are implicitly selected without aliasing, it can lead to conflicts. More critically, if a parameter name (`user_id`) matches a returned column name and they are derived from different sources, it can be ambiguous.

3

Explicitly alias all columns within the `RETURN` statement of a table-valued function or within the SELECT statements of a procedure to ensure uniqueness, especially when input parameters might share names.

Corrected function example:

sql
CREATE FUNCTION get_user_data (p_user_id INT)
RETURNS TABLE (u_id INT, user_name VARCHAR(100))
AS
BEGIN
    RETURN SELECT user_id AS u_id, name AS user_name FROM users WHERE id = :p_user_id;
END;

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Related Errors

5 related errors

SAP S/4HANA Error 1329: SQLScript Duplicate Column Name