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How to do a FULL OUTER JOIN in MySQL?
I want to do a Full Outer Join in MySQL. Is this possible? Is a Full Outer Join supported by MySQL?
15 Answers
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Get table names using SELECT statement in MySQL
In MySQL, I know I can list the tables in a database with:
12 Answers
12
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What is the benefit of zerofill in MySQL?
...ow what is the benefit/usage of defining ZEROFILL for INT DataType in MySQL ?
9 Answers
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How do I show a MySQL warning that just happened?
I just ran a simple MySQL CREATE TABLE statement that produced the line
3 Answers
3
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Invalid default value for 'create_date' timestamp field
...t ignore this option. This is server option. If you have access to my.ini (mysql configuration file), then remove NO_ZERO_DATE from sql-mode option and restart server.
– Devart
Feb 8 '12 at 11:44
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MySQL “Group By” and “Order By”
... non-aggregate columns in a SELECT with a GROUP BY clause is non-standard. MySQL will generally return the values of the first row it finds and discard the rest. Any ORDER BY clauses will only apply to the returned column value, not to the discarded ones.
IMPORTANT UPDATE
Selecting non-aggregate col...
【BLE技术内幕】BLE技术揭秘 - 创客硬件开发 - 清泛IT论坛，有思想、有深度
...个时间点把数据包发送出去，怎么保证数据的完整性，ACK如何接收，如何进行重传，以及如何对链路进行管理和控制等等。LL层只负责把数据发出去或者收回来，对数据进行怎样的解析则交给上面的GAP或者ATTHost Controller Interface，...
Set value to NULL in MySQL
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You're probably quoting 'NULL'. NULL is a reserved word in MySQL, and can be inserted/updated without quotes:
INSERT INTO user (name, something_optional) VALUES ("Joe", NULL);
UPDATE user SET something_optional = NULL;
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select * vs select column
...the top of my head is when you want only the value of an indexed column in MySQL (for example, just to check for row existence), and you're using MyISAM storage engine, it'll grab the data from the MYI file, which could be in memory, and not even go to disk!
– Mike Sherov
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MySQL ON DUPLICATE KEY - last insert id?
...heck this page out: https://web.archive.org/web/20150329004325/https://dev.mysql.com/doc/refman/5.0/en/insert-on-duplicate.html
At the bottom of the page they explain how you can make LAST_INSERT_ID meaningful for updates by passing an expression to that MySQL function.
From the MySQL documentation...