alter table in stored procedure

CREATE PROCEDURE ppg_gc (IN expiryTime INTEGER, IN batchSize INTEGER)
LANGUAGE SQL
MODIFIES SQL DATA
BEGIN


declare v_stmt varchar(20);
--now store ur query inside this variable,then prepare the statement.

v_stmt = 'alter table emp drop primary key';
prepare S1 from v_stmt;
EXECUTE IMMEDIATE S1;

END @


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