What is the method to remove duplicate rows in SQL Serv…

In SQL Server, you can use the following methods to remove duplicate rows:

1. Use the DISTINCT keyword: Use the SELECT DISTINCT statement to select all unique rows. For example:

SELECT DISTINCT column1, column2, ...
FROM table_name;

1. Grouping rows together with the GROUP BY clause allows you to select one row from each group. For example:

SELECT column1, column2, ...
FROM table_name
GROUP BY column1, column2, ...;

1. Utilize the ROW_NUMBER function: Assign a unique number to each row using the ROW_NUMBER function, then select the row with the number 1. For example:

WITH CTE AS (
    SELECT column1, column2, ..., ROW_NUMBER() OVER (PARTITION BY column1, column2, ... ORDER BY column1) AS row_num
    FROM table_name
)
SELECT column1, column2, ...
FROM CTE
WHERE row_num = 1;

Note: column1, column2, etc. in the above methods represent the column names to be deduplicated, and table_name represents the table name to be deduplicated.