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Export and Import all MySQL databases at one time
I want to keep a backup of all my MySQL databases. I have more than 100 MySQL databases. I want to export all of them at the same time and again import all of them into my MySQL server at one time. How can I do that?
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MySQL root password change
I have been trying to reset my MySQL root password. I have run the mysqld_safe --skip-grant-tables, updated the root password, and checked the user table to make sure it is there. Once restarting the mysql daemon I tried logging in with the new root password that I just set and still get Access de...
How to randomly select rows in SQL?
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SELECT TOP 5 Id, Name FROM customerNames
ORDER BY NEWID()
That said, everybody seems to come to this page for the more general answer to your question:
Selecting a random row in SQL
Select a random row with MySQL:
SELECT...
Return a value if no rows are found in Microsoft tSQL
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SELECT CASE WHEN COUNT(1) > 0 THEN 1 ELSE 0 END AS [Value]
FROM Sites S
WHERE S.Id = @SiteId and S.Status = 1 AND
(S.WebUserId = @WebUserId OR S.AllowUploads = 1)
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初窥InnoDB的Memcached插件 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...插件目录我们能看到innodb_engine.so和libmemcached.so：
mysql> SELECT @@plugin_dir;
+------------------------------+
| @@plugin_dir |
+------------------------------+
| /usr/local/mysql/lib/plugin/ |
+------------------------------+
此外还需要导入Memcached插...
What is the PostgreSQL equivalent for ISNULL()
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SELECT CASE WHEN field IS NULL THEN 'Empty' ELSE field END AS field_alias
Or more idiomatic:
SELECT coalesce(field, 'Empty') AS field_alias
share...
转：postfix安装Q&A - 更多技术 - 清泛网 - 专注C/C++及内核技术
... QUOTE:
Q：
Jan 13 11:26:29 mail authdaemond: failed to connect to mysql server (server=localhost , userid=postfix ): Unknown MySQL server host 'localhost ' (2)
Jan 13 11:26:29 mail postfix/smtpd[2829]: warning: SASL authentication failure: could not verify password
Jan 13 12:11:19 mai...
MongoDB: Combine data from multiple collections into one..how?
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Doing unions in MongoDB in a 'SQL UNION' fashion is possible using aggregations along with lookups, in a single query. Here is an example I have tested that works with MongoDB 4.0:
// Create employees data for testing the union.
d...
How do I create a user with the same privileges as root in MySQL/MariaDB? [closed]
How do I create a user with the same privileges as root in MySQL/MariaDB?.
1 Answer
1...
What are the use cases for selecting CHAR over VARCHAR in SQL?
...'123 Main St Washington, MD 12345', 123.45)
create view vwStagingTable AS
SELECT CustomerFirstName = CAST(CustomerFirstName as CHAR(30)),
CustomerLastName = CAST(CustomerLastName as CHAR(30)),
CustomerCityStateZip = CAST(CustomerCityStateZip as CHAR(100)),
CustomerCurrentBalance = CAST(CAST(Custome...