> alter tableの構文が覚えられない
*** カラム追加 [#r4034686]
alter table <table name> add column <column name> text;
*** not null追加 [#u5998b9b]
alter table <table name> alter column <column name> set not null;
*** not null除去 [#l306f5a9]
alter table <table name> alter column <column name> drop not null;
*** default 追加 [#z620cd91]
alter table <table name> alter column <column name> set default 'hello';
*** default削除 [#zd540b91]
alter table <table name> alter column <column name> drop default;
*** 外部キー追加 [#s01352dc]
alter table <table name> add constraint <key name> FOREIGN KEY( <column name>) references <table name>( <column name> );
*** 外部キー変更（delete cascade付与） [#yd13fc69]
alter table <table name> drop constraint <key name>, add constraint <key name> foreign key (<column name>) references <table name>( column name>) on delete cascade;
*** 外部キー除去 [#c2511ab1]
alter table <table name> drop constraint <key name>;
*** uniqueキー追加 [#i3ccf08e]
alter table <table name> add constraint <key name> unique (<columns...>);
*** カラム名変更 [#h88808c9]
alter table <table name> rename column <old name> to <new name>;
*** プライマリーキー削除 [#u25bbb36]
alter table <table name> drop constraint <key name>;
*** プライマリーキー追加 [#hd2dccb6]
alter table <table name> add primary key (<columns...>);
*** delete cascade追加 [#k39f11cc]
alter table <table> drop constraint <key>, add constraint <key> foreign key (<column>) references <table>(<column>) on delete cascade;