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MySQL - Using COUNT(*) in the WHERE clause
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try this;
select gid
from `gd`
group by gid
having count(*) > 10
order by lastupdated desc
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Simulating group_concat MySQL function in Microsoft SQL Server 2005?
...sy way to do this. Lots of ideas out there, though.
Best one I've found:
SELECT table_name, LEFT(column_names , LEN(column_names )-1) AS column_names
FROM information_schema.columns AS extern
CROSS APPLY
(
SELECT column_name + ','
FROM information_schema.columns AS intern
WHERE extern....
How to find the kth smallest element in the union of two sorted arrays?
...ithmic. (Here we are getting rid of half). In order to do that, we need to select one array whose one of the halves we can safely ignore. How do we do that? By confidently eliminating the half we know for sure is not going to have the kth element.
– lambdapilgrim
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Convert timestamp to date in MySQL query
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SELECT * FROM users WHERE DATE_FORMAT(FROM_UNIXTIME(users.user_created_at),'%Y-%b-%e') = '2015-03-06' is this correct format or should i modify this?
– Dheeraj Thedijje
Mar 7 '18 at 11:4...
Cast int to varchar
...datatype, there is no varchar datatype that you can cast/convert data to:
select CAST(id as CHAR(50)) as col1
from t9;
select CONVERT(id, CHAR(50)) as colI1
from t9;
See the following SQL — in action — over at SQL Fiddle:
/*! Build Schema */
create table t9 (id INT, name VARCHAR(55));
ins...
能否详细说明下数据库的应用？ - App Inventor 2 中文网 - 清泛IT社区，为创新赋能！
...说明太少，比如哪里有云数据库的提供商，或者云数据库如何私有部署，能否详细说说，我想很多人应该有网络数据库的需求的，比如1个多客户的登录。非常感谢！网络微数据库已经出过不少资料了，详见中文文档页面：https://...
How to Get True Size of MySQL Database?
... would like to know how much space does my MySQL database use, in order to select a web host.
I found the command SHOW TABLE STATUS LIKE 'table_name' so when I do the query, I get something like this:
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Convert MySql DateTime stamp into JavaScript's Date format
...d.
A MySQL DATETIME column can be converted to a unix timestamp through:
SELECT unix_timestamp(my_datetime_column) as stamp ...
We can make a new JavaScript Date object by using the constructor that requires milliseconds since the epoch. The unix_timestamp function returns seconds since the epoc...
“Incorrect string value” when trying to insert UTF-8 into MySQL via JDBC?
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The second approach should be used selectively, i. e. never be applied to SELECT queries, as set names utf8mb4; select ... from ... will never produce a ResultSet and instead result in a ResultSet is from UPDATE. No Data. error.
– Bass
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How to change collation of database, table, column?
...he OP asked:
How to change collation of database, table, column?
The selected answer just states it on table level.
Changing it database wide:
ALTER DATABASE <database_name> CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
Changing it per table:
ALTER TABLE <table_name> CON...