WebAug 14, 2024 · Many times, our database contains duplicate rows which can be filtered out using certain columns. This can happen for many reasons like bad data import, wrong … Web#SQL#Traning#Youtuber#Interview questions@dataengineer@data analyst

Delete Duplicate Record From SQL Database Using CTE

WebFeb 13, 2009 · delete from cte_duplicate where rownumber<>1 If we again see the data in the table tbl_dublicatedata using the same query which we used earlier we will get the … WebSep 19, 2024 · This method uses a LEFT OUTER JOIN from the table that has the records to delete, to a subquery that contains the duplicate records. DELETE ( SELECT d.*, d.rowid FROM customer d LEFT OUTER JOIN ( SELECT MIN(RowId) AS MinRowId, first_name, last_name, address FROM customer GROUP BY first_name, last_name, … purple layered dress

Delete Duplicate Records Using CTE - c-sharpcorner.com

WebAug 19, 2024 · Since you have no primary key you may (ab)use the ctid pseudo column to identify the rows to delete. WITH cte AS ( SELECT ctid, row_number () OVER (PARTITION BY voter, election_year ORDER BY voter) rn FROM votes ) DELETE FROM votes USING cte WHERE cte.rn > 1 AND cte.ctid = votes.ctid; db<>fiddle. And probably think about … WebJan 19, 2024 · Sorted by: 6. If you just want to return the most recent row for name, you can use: select t.* from t where t.date = (select max (t2.date) from t t2 where t2.name = t.name); In most databases, you can use similar logic for a delete: delete from t where t.date < (select max (t2.date) from t t2 where t2.name = t.name) Share. Improve this answer. WebLearn how to use a CTE to delete duplicate rows from a SQL Table. I'll be demonstrating this in SQL Server but the concepts are universal across most Relatio... purple leaf air freshener