-- Assuming you have a table called `your_table` with columns: `column1`, `column2`, ...

​

-- Insert query to duplicate the row with a specific condition

INSERT INTO your_table (column1, column2, ...)

SELECT column1, column2, ...

FROM your_table

WHERE your_condition;

​

-- Example: Duplicate the row with ID = 1

INSERT INTO your_table (column1, column2, ...)

SELECT column1, column2, ...

FROM your_table

WHERE ID = 1;

SELECT _column, COUNT(*) 

FROM _table

GROUP BY _column

HAVING COUNT(*) > 1

Multiple field=

SELECT username, email, COUNT(*)

FROM users

GROUP BY username, email

HAVING COUNT(*) > 1

​

Single field=

SELECT _column, COUNT(*) 

FROM _table

GROUP BY _column

HAVING COUNT(*) > 1

SELECT column1, column2, COUNT(*)

FROM table_name

GROUP BY column1, column2

HAVING COUNT(*) > 1;

SELECT DISTINCT col1,col2... FROM table_name where Condition;

SELECT column_name, COUNT(*)

FROM table_name

GROUP BY column_name

HAVING COUNT(*) > 1;

SELECT OrderID, COUNT(OrderID)

FROM Orders

GROUP BY OrderID

HAVING COUNT(OrderID) > 1

SELECT *

INTO NewTableName

FROM OriginalTable;

/*SELECT hotel_id, reservation_id, COUNT(hotel_id)FROM staywhere  reservation_id is not nullGROUP BY hotel_id, reservation_idHAVING COUNT(hotel_id) > 1*/select distinct s.hotel_id , t.* from stay sright join (    select hotel_id, reservation_id, count(*) as qty    from staywhere reservation_id !=1      group by hotel_id, reservation_id    having count(*) > 1) t on s.hotel_id = t.hotel_id and s.reservation_id = t.reservation_id