大约有 40,000 项符合查询结果（耗时：0.0239秒） [XML]
Get records with max value for each group of grouped SQL results
...
There's a super-simple way to do this in mysql:
select *
from (select * from mytable order by `Group`, age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. T...
App Inventor 2 PrivacyPolicyAI2Ext 拓展：隐私政策弹窗、隐私确认弹窗 ·...
...后，会记住这个状态，后续就不再弹窗提醒。App升级不会重置这个状态，只有在App卸载后重新安装，才能重新提醒。
隐私政策网页
如果有自己的网站那是最好，没有的话一般采用托管的方式：
托...
MySQL ON vs USING?
...n tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a column of the exact same name on which they join. In this case, one may say:
SELECT ... FR...
Is there a MySQL command to convert a string to lowercase?
...nction is LOWER() or LCASE() (they both do the same thing).
For example:
select LOWER(keyword) from my_table
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MySQL: Quick breakdown of the types of joins [duplicate]
...es
END EDIT
In a nutshell, the comma separated example you gave of
SELECT * FROM a, b WHERE b.id = a.beeId AND ...
is selecting every record from tables a and b with the commas separating the tables, this can be used also in columns like
SELECT a.beeName,b.* FROM a, b WHERE b.id = a.beeId...
Log all queries in mysql
...global general_log = 1;
SET global log_output = 'table';
View the log
select * from mysql.general_log
Disable Query logging on the database
SET global general_log = 0;
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Remove DEFINER clause from MySQL Dumps
I have a MySQL dump of one of my databases. In it, there are DEFINER clauses which look like,
24 Answers
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How to get the sizes of the tables of a MySQL database?
...he size of a table (although you need to substitute the variables first):
SELECT
table_name AS `Table`,
round(((data_length + index_length) / 1024 / 1024), 2) `Size in MB`
FROM information_schema.TABLES
WHERE table_schema = "$DB_NAME"
AND table_name = "$TABLE_NAME";
or this query ...
Fastest Way to Find Distance Between Two Lat/Long Points
...ate a SPATIAL index on these points
Use MBRContains() to find the values:
SELECT *
FROM table
WHERE MBRContains(LineFromText(CONCAT(
'('
, @lon + 10 / ( 111.1 / cos(RADIANS(@lon)))
, ' '
, @lat + 10 / 111.1
, ','
, @lon - 10 / ( 111.1 / cos(RADI...
How to select records from last 24 hours using SQL?
...
SELECT *
FROM table_name
WHERE table_name.the_date > DATE_SUB(CURDATE(), INTERVAL 1 DAY)
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