MySQL cursors use BULK INSERT or update data

--Loop loops

CREATE PROCEDURE ' test '. ' New_procedure ' () begin--need to define a variable that receives cursor data   DECLARE a CHAR (+);  --Cursor  DECLARE cur cursor for SELECT i from test.t;  --Traversal data end flag  DECLARE done INT DEFAULT FALSE;  --binds the end flag to the cursor  DECLARE CONTINUE HANDLER for not FOUND SET do = TRUE;  --Opening the cursor open  cur;    --Start loop  read_loop:loop    --Extract the data from the cursor, there is only one, and many words are the same;    FETCH cur into A;    --When the declaration is finished, IF done then      LEAVE read_loop;    END IF;    --Here do the loop events you want to do    INSERT into test.t VALUES (a);  END LOOP;  --Closing the cursor close  cur;
END;

Note: the definition of a variable does not have the same name as the key of your select column! Otherwise, fetch into will fail!

Other than that:

If not, insert the data if there is an updated method:

INSERT INTO ' test ' values (A, B) on DUPLICATE KEY UPDATE ' a ' =c;

--While loop

CREATE PROCEDURE Curdemo () BEGIN       Declare stop_flag int default 0;//declares a tag when the cursor state is the last record, modify the variable declare ID int default 0 ;d eclare type int default 0;declare order1 int default 0;declare CUR1 cursor FOR SELECT * from Test1;       Declare CONTINUE HANDLER for SQLSTATE ' 02000 ' SET stop_flag=1;         Open cur1;//cursor       fetch cur1 into id,type,order1; Read data to Cursor while       stop_flag<>1 do//if cursor has next record, loop insert INTO t     Est2 values (id,type,order1);      Fetch cur1 into id,type,order1;       End While;       Close cur1;//closes the cursor end;

MySQL cursors use BULK INSERT or update data