MySQL Delete duplicates only keep one bar

The barcode value that would have been deleted in the Error_barcode table is repeated only one table structure as follows (Ps:id is self-growing, the figure is deleted successfully so ID is not contiguous)

The SQL statements are as follows:

DELETE fromError_barcodeWHEREBarCodeinch (        SELECTBarCode fromError_barcodeGROUP  byBarCode having            Count(BarCode)> 1    ) andId not inch (    SELECT        min(ID) fromError_barcodeGROUP  byBarCode having        Count(BarCode)> 1)

But it's a mistake.

Surfing the internet to find the next, this is a problem with MySQL, is no longer in the same statement to the same table first select some values in the update,

Then you need the handle. Queries are placed into a subquery

DELETE  fromError_barcodeWHEREBarCodeinch(    SelectA.barcode from(Select *  fromError_barcode) AGROUP  byBarCode having Count(BarCode)>1) andId not inch (    Select min(ID) from(Select *  fromError_barcode) bGROUP  byBarCode having Count(BarCode)>1)

Can see I put the following two sub-queries

SELECT             barCode        from            error_barcode        GROUP by             BarCode        have            count>1

SELECT        min (ID)      from         error_barcode    GROUPby        barcode    have        count>1

Change into

 select  a.barcode from  (select  *  from  Error _barcode) a group  by  barcode having  count  (barCode)   1  

Select min  from (Select* from Error_barcode) b  GROUPby havecount (BarCode)>1

It's all right.

MySQL Delete duplicates only keep one bar