Shulou(Shulou.com)06/01 Report--

Create a test table

Create table t1.t (an int,b varchar)

-- add primary key, index

Alter table t1.t add primary key (a)

Alter table t1.t add index ind_t_a (a)

-- Delete primary keys and indexes

Alter table t1.t drop primary key

Alter table t1.t drop index ind_t_a

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