Oracle 主键自增长

Table：

CREATE TABLE TEST_A    (        ID NUMBER NOT NULL,        NAME CHAR(200),        ADDRESS CHAR(200),        CONSTRAINT ID PRIMARY KEY (ID)    )

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Sequence:

create sequence S_TEST_Aminvalue 1maxvalue 9999999999999999999999999999start with 21increment by 1cache 20;

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Trigger:

create or replace trigger "test_a_trigger" beforeinsert on TEST_A for each row when (new.id is null)begin     select S_TEST_A.nextval into:new.id from dual;end;

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