大约有 7,000 项符合查询结果（耗时：0.0367秒） [XML]
How do I find which transaction is causing a “Waiting for table metadata lock” state?
...ransactions waiting for locks:
SELECT TRX_ID, TRX_REQUESTED_LOCK_ID, TRX_MYSQL_THREAD_ID, TRX_QUERY
FROM INNODB_TRX
WHERE TRX_STATE = 'LOCK WAIT';
Reference - MySQL Troubleshooting: What To Do When Queries Don't Work, Chapter 6 - Page 96.
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ALTER TABLE without locking the table?
When doing an ALTER TABLE statement in MySQL, the whole table is read-locked (allowing concurrent reads, but prohibiting concurrent writes) for the duration of the statement. If it's a big table, INSERT or UPDATE statements could be blocked for a looooong time. Is there a way to do a "hot alter", li...
MySQL: What's the difference between float and double?
...someone changed a field from float to double. Wondering why, I checked the mysql documentation, but honestly didn't understand what the difference is.
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mysql query order by multiple items
..._activity ASC so sort direction for each column, default sort direction in mysql (with default configuration) is ASC.
– ZurabWeb
Jan 30 '14 at 20:29
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MySql - Way to update portion of a string?
I'm looking for a way to update just a portion of a string via MySQL query.
4 Answers
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MySQL: Sort GROUP_CONCAT values
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Sure, see http://dev.mysql.com/doc/refman/...tions.html#function_group-concat:
SELECT student_name,
GROUP_CONCAT(DISTINCT test_score ORDER BY test_score DESC SEPARATOR ' ')
FROM student
GROUP BY student_name;
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How to find gaps in sequential numbering in mysql?
... SELECT @var:= max FROM ....; select * from .. WHERE seq < @max; with MySQL variables.
– Moshe L
Mar 25 '19 at 6:08
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MySQL Select minimum/maximum among two (or more) given values
...1) AS date1
FROM A, B
WHERE B.x = A.x
Both are described here http://dev.mysql.com/doc/refman/5.0/en/comparison-operators.html
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Is there any connection string parser in C#?
...on string builders from various providers like SqlConnectionStringBuilder, MySqlConnectionStringBuilder, SQLiteConnectionStringBuilder etc (unfortunately there is no public interface from MS this time). Otherwise you have DbProviderFactory.CreateConnectionStringBuilder which will give you an alterna...
File Hash 扩展：文件哈希计算和 Base64 编码文件，sha256、sha512 哈希 ·...
...全文件传输验证
备份文件一致性检查
文件去重比较
密码存储（建议使用加盐哈希）
相关功能
可以使用 Juan Antonio 的 Terminal 扩展 通过 Linux 命令获取文件的 SHA256 哈希：
sha256sum /absolute/path/to/file
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