sqlite
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alter
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vt. old
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ALTER TABLE Database_name.table_name RENAME TO new_table_name;
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ALTER TABLE ??????_??.???_?? ADD COLUMN ??_def...;
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COMPANY 表有如下記錄: ID NAME AGE ADDRESS SALARY ---------- ---------- ---------- ---------- ---------- 1 Paul 32 California 20000.0 2 Allen 25 Texas 15000.0 3 Teddy 23 Norway 20000.0 4 Mark 25 Rich-Mond 65000.0 5 David 27 Texas 85000.0 6 Kim 22 South-Hall 45000.0 7 James 24 Houston 10000.0 現(xiàn)在,讓我們嘗試使用 ALTER TABLE 語句重命名該表,如下所示: sqlite> ALTER TABLE COMPANY RENAME TO OLD_COMPANY; 上面的 SQLite 語句將重命名 COMPANY 表為 OLD_COMPANY。現(xiàn)在,讓我們嘗試在 OLD_COMPANY 表中添加一個新的列,如下所示: sqlite> ALTER TABLE OLD_COMPANY ADD COLUMN SEX char(1); 現(xiàn)在,COMPANY 表已經(jīng)改變,使用 SELECT 語句輸出如下: ID NAME AGE ADDRESS SALARY SEX ---------- ---------- ---------- ---------- ---------- --- 1 Paul 32 California 20000.0 2 Allen 25 Texas 15000.0 3 Teddy 23 Norway 20000.0 4 Mark 25 Rich-Mond 65000.0 5 David 27 Texas 85000.0 6 Kim 22 South-Hall 45000.0 7 James 24 Houston 10000.0 請注意,新添加的列是以 NULL 值來填充的。