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How do I convert from BLOB to TEXT in MySQL?

... That's unnecessary. Just use SELECT CONVERT(column USING utf8) FROM..... instead of just SELECT column FROM... share | improve this answer | ...
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Differences between INDEX, PRIMARY, UNIQUE, FULLTEXT in MySQL?

...e - which are typically implemented internally using b-trees (allowing for selecting, sorting or ranges starting from left most column) or hash tables (allowing for selection starting from left most column). Where the other index types are general-purpose, a FULLTEXT index is specialised, in that it...
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Duplicating a MySQL table, indices, and data

...ese 2 queries: CREATE TABLE newtable LIKE oldtable; INSERT INTO newtable SELECT * FROM oldtable; To copy just structure and data use this one: CREATE TABLE tbl_new AS SELECT * FROM tbl_old; I've asked this before: Copy a MySQL table including indexes ...
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How to update column with null value

...Hello'); UPDATE your_table SET your_column = NULL WHERE some_id = 1; SELECT * FROM your_table WHERE your_column IS NULL; +---------+-------------+ | some_id | your_column | +---------+-------------+ | 1 | NULL | +---------+-------------+ 1 row in set (0.00 sec) ...
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搭建高可用mongodb集群(三)—— 深入副本集内部机制 - 大数据 & AI - 清...

...着副本集的问题来看吧! 副本集故障转移,主节点是如何选举的?能否手动干涉下架某一台主节点。 官方说副本集数量最好是奇数,为什么? mongodb副本集是如何同步的?如果同步不及时会出现什么情况?会不会出现不一致...
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MySQL: Set user variable from result of query

...need to move the variable assignment into the query: SET @user := 123456; SELECT @group := `group` FROM user WHERE user = @user; SELECT * FROM user WHERE `group` = @group; Test case: CREATE TABLE user (`user` int, `group` int); INSERT INTO user VALUES (123456, 5); INSERT INTO user VALUES (111111...
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Import CSV to mysql table

What is the best/fastest way to upload a csv file into a mysql table? I would like for the first row of data be used as the column names. ...
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How do I query between two dates using MySQL?

...ember 29 2010 and January 30 2010). Try reversing the order of the dates: SELECT * FROM `objects` WHERE (date_field BETWEEN '2010-01-30 14:15:55' AND '2010-09-29 10:15:55') share | improve this an...
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StatusbarTools 扩展 - 状态栏自定义工具 · App Inventor 2 中文网

... 刷新状态栏() 刷新状态栏显示,应用最新的设置。 重置设置() 重置所有状态栏设置为默认值。 使用示例 基本颜色设置 when Screen1.Initialize do // 设置状态栏为蓝色背景 call StatusbarT...
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With MySQL, how can I generate a column containing the record index in a table?

... You may want to try the following: SELECT l.position, l.username, l.score, @curRow := @curRow + 1 AS row_number FROM league_girl l JOIN (SELECT @curRow := 0) r; The JOIN (SELECT @curRow := 0) part allows the variable initiali...