under the separation of mysql read and write, is, select for update/lock in share mode performed in the read library or the write library?
under the separation of mysql read and write, is, select for update/lock in share mode performed in the read library or the write library?
write to the library, because the main lock is writing
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tb_user (user information) id tb_article (article information) id, foreign key user_id-> tb_user.id tb_comment (comment information) id, foreign key user_id-> tb_user.id query the top 5 users of the latest article or comment. order by tb_article.cre...
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Today we have a problem with a compound primary key, which ensures that multiple column combinations are not unique. But in practice, it s the opposite. this is my table structure 12342,2,1: wonder ...
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CREATE OR REPLACE PROCEDURE QD_MYDTJ (BEGINDATE VARCHAR2, ENDDATE VARCHAR2, xz_name VARCHAR2, xz_number VARCHAR2, --BEGININTEVAL VARCHAR2, --ENDINTEVAL VARCHAR2, start1 IN NUMBER, limit1 IN NUMBER, AN_O_RET_CODE ...
in a transactional method, by reading a collection of table records and cycling the values of update or save fields, the administrative account is updated every time an ordinary account is updated. so re-query the system account . @Transactional(rollba...
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problem description String [] str = { "mysqldump -h localhost -u root -p -t lailr_js_pay wx_sp > f: test.sql" ,"root" }; Runtime.getRuntime (str) .exec executes the mysqldump command to generate the sql file...