增量表能夠生成標識列，如下所示：
CREATE TABLE TestMe (
pKey bigint GENERATED ALWAYS AS IDENTITY (START WITH 1 INCREMENT BY 1),
id bigint,
commentary string
)
USING DELTA
OPTIONS (PATH "/mnt/Delta/Testing/TestMe")
但是，如果不手動編輯似乎有風險的變更日志檔案，似乎沒有辦法重置計數器。
如果我想截斷表并在其中放置一組新資料，我怎么能做到這一點而不慢慢累積數億/數十億的標識列（插入計數器的每個資料都只會上升并且永遠不會重置）？
uj5u.com熱心網友回復：
請嘗試這種方式
CREATE TABLE TestMe (
pKey bigint GENERATED ALWAYS AS IDENTITY (START WITH 1 INCREMENT BY 1),
id bigint,
commentary string
);
insert into TestMe (id,commentary) values (1,'a'),(2,'b'),(3,'c');
select * from TestMe;
truncate table TestMe;
describe history TestMe;
Restore Table TestMe to version as of 0;
insert into TestMe (id,commentary) values (1,'a'),(2,'b'),(3,'c');
uj5u.com熱心網友回復：
找到了另一種解決方法
CREATE or REPLACE TABLE TestMe (
pKey bigint GENERATED ALWAYS AS IDENTITY (START WITH 1 INCREMENT BY 1),
id bigint,
commentary string
);
insert into TestMe (id,commentary) values (1,'a'),(2,'b'),(3,'c');
select * from TestMe;
-- Rerun Create or Replace resets the identity
CREATE or REPLACE TABLE TestMe (
pKey bigint GENERATED ALWAYS AS IDENTITY (START WITH 1 INCREMENT BY 1),
id bigint,
commentary string
);
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