SQL?? ?? ???? ??? ??????

SQL?? ?? ???? ??? ??????

SQL??? alter table ?? ???? ?? ??? ? ????. ??? ??? ????. alter table table_name drop column column_name. SQL? ?? ? ??? ?? ??? ? ?? ??? ??? ?????.

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???? ??：Apr 29, 2024 pm 04:57 PM

SQL??? ALTER TABLE ?? ???? ??? ?????. ??? ??? ????. ALTER TABLE ???_?? DROP COLUMN ??_??; ??? ??? ????. ② ??? ??? ??? ??? ?????. ??? ??; ③ ???? ?????. ?? ?? ?? ????? ??? ?? ????? ???? ??? ????. ALTER TABLE ?? DROP COLUMN ??? ? ??? ??? ? ?? ???? ?? ?? ?? ??? ???? ??? ?? ? ????.

Apr 29, 2024 pm 01:15 PM

SQL?? ???? ???? ???? ??? ????.

SQL?? ???? ???? ? ???? ?? DROP TABLE???. ??? DROP TABLE table_name???. ? ???? ??? ???? ???? ???? ????? ?????.

Apr 29, 2024 pm 01:48 PM

SQL?? ?? ???? ??

SQL?? ?? ???? ??? DROP VIEW [schema_name.]view_name;???. ? ??? ??? Schema_name?? view_name??? ?? ????? ?? ???? ???? ???? ????. ?? ???? ?? ?? ?? ??? ???? ??? ?? ???? ???.

Apr 29, 2024 pm 01:33 PM

SQL?? ???? ???? ??? ??????

???? ???? SQL ??? DROP TABLE???. ? ??? ??? ??? ???? ???? ?????. ??? ??? ????. DROP TABLE table_name. ???? ????? ?? ???? ?? ???? ???? ??? ??? ??? ? ????? ????? ????. ???? ?? ?? ???? ???? ?? ????.

Apr 28, 2024 am 10:21 AM

SQL?? ???? ???? ??

DELETE ?? ???? ????? ???? ?????. DELETE ?? ??? ??? ????. DELETE FROM table_name WHERE ??. ??? table_name? ??? ???? ??? ??? ?? ?????. ??? ???? ??? ???? ?? ???? ?????.

Apr 28, 2024 am 09:09 AM