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MySQL: Fastest way to count number of rows
...s.
The solution is SQL_CALC_FOUND_ROWS. This is usually used when you are selecting rows but still need to know the total row count (for example, for paging).
When you select data rows, just append the SQL_CALC_FOUND_ROWS keyword after SELECT:
SELECT SQL_CALC_FOUND_ROWS [needed fields or *] FROM t...
Schrödingers MySQL table: exists, yet it does not
...or if you have backups, try the following:
Delete all schemas (excluding mysql)
shut down the database
Make sure that all folders in your data directory have been removed properly (again, excluding mysql)
delete ibdata and log files
restart the database. It should recreate the tablespace and logs ...
Why is '+' not understood by Python sets?
...ts don't have an implementation for the + operator.
You can use | for set union and & for set intersection.
Sets do implement - as set difference. You can also use ^ for symmetric set difference (i.e., it will return a new set with only the objects that appear in one set but do not appear in b...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...'t, then use DISTINCT.
GROUP BY in MySQL sorts results. You can even do:
SELECT u.profession FROM users u GROUP BY u.profession DESC
and get your professions sorted in DESC order.
DISTINCT creates a temporary table and uses it for storing duplicates. GROUP BY does the same, but sortes the disti...
Composer killed while updating
...out, don't forget to add sudo if you don't work as root.
btw, feel free to select another location/filename/size for the file.
/var is probably not the best place, but I don't know which place would be, and rarely care since tiny servers are mostly used for testing purposes.
...
Get table names using SELECT statement in MySQL
...
To get the name of all tables use:
SELECT table_name FROM information_schema.tables;
To get the name of the tables from a specific database use:
SELECT table_name FROM information_schema.tables
WHERE table_schema = 'your_database_name';
Now, to answer the...
How to remove all MySQL tables from the command-line without DROP database permissions? [duplicate]
...tatements to execute it:
SET FOREIGN_KEY_CHECKS = 0;
SET @tables = NULL;
SELECT GROUP_CONCAT('`', table_schema, '`.`', table_name, '`') INTO @tables
FROM information_schema.tables
WHERE table_schema = 'database_name'; -- specify DB name here.
SET @tables = CONCAT('DROP TABLE ', @tables);
PRE...
App Inventor 2 拓展参考文档 · App Inventor 2 中文网
...理
【FTP】App Inventor 2 FTP 上传下载全方案总结
【MD5、密码安全】Encrypt.Security 安全性扩展：MD5哈希，SHA1和SHA256哈希，AES加密/解密，RSA加密/解密，BASE64编码/解码
【AES加解密】MareshaAES 拓展：AES加解密算法
【CRC校验】App Inven...
MySQL order by before group by
... table on both the post_author and the max date.
The solution should be:
SELECT p1.*
FROM wp_posts p1
INNER JOIN
(
SELECT max(post_date) MaxPostDate, post_author
FROM wp_posts
WHERE post_status='publish'
AND post_type='post'
GROUP BY post_author
) p2
ON p1.post_author = p...
Disable ONLY_FULL_GROUP_BY
...ove ONLY_FULL_GROUP_BY from mysql console
mysql > SET GLOBAL sql_mode=(SELECT REPLACE(@@sql_mode,'ONLY_FULL_GROUP_BY',''));
you can read more here
Solution 2: Remove ONLY_FULL_GROUP_BY from phpmyadmin
Open phpmyadmin & select localhost
Click on menu Variables & scroll down for sq...