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How to DROP multiple columns with a single ALTER TABLE statement in SQL Server?
...DROP { [ CONSTRAINT ] constraint_name | COLUMN column } [ ,...n ]
For MySQL:
ALTER TABLE TableName
DROP COLUMN Column1,
DROP COLUMN Column2;
or like this1:
ALTER TABLE TableName
DROP Column1,
DROP Column2;
1 The word COLUMN is optional and can be omitted, except for RENAME...
SQL Server equivalent of MySQL's NOW()?
I'm a MySQL guy working on a SQL Server project, trying to get a datetime field to show the current time. In MySQL I'd use NOW() but it isn't accepting that.
...
How to get disk capacity and free space of remote computer
...t Win32_LogicalDisk -ComputerName remotecomputer -Filter "DeviceID='C:'" |
Select-Object Size,FreeSpace
$disk.Size
$disk.FreeSpace
To extract the values only and assign them to a variable:
$disk = Get-WmiObject Win32_LogicalDisk -ComputerName remotecomputer -Filter "DeviceID='C:'" |
Foreach-Obje...
Android studio add external project to build.gradle
...ick module -> Open Module Settings -> Dependencies -> + (bottom), select Module Dependency, select your library from the list, click ok :)
– T.Coutlakis
Jan 11 '15 at 22:51
...
What is the string concatenation operator in Oracle?
...
It is ||, for example:
select 'Mr ' || ename from emp;
The only "interesting" feature I can think of is that 'x' || null returns 'x', not null as you might perhaps expect.
...
LEFT JOIN only first row
...rtist_id) will be the earliest.
So try something like this (untested...)
SELECT *
FROM feeds f
LEFT JOIN artists a ON a.artist_id = (
SELECT
MIN(fa.artist_id) a_id
FROM feeds_artists fa
WHERE fa.feed_id = f.feed_id
) a
...
How can I modify the size of column in a MySQL table?
... MODIFY command can do this more concisely.
Re the MEDIUMTEXT thing: a MySQL row can be only 65535 bytes (not counting BLOB/TEXT columns). If you try to change a column to be too large, making the total size of the row 65536 or greater, you may get an error. If you try to declare a column of V...
PDO MySQL扩展模块 检测通不过的解决方法 - 更多技术 - 清泛网 - 专注C/C++及内核技术
PDO MySQL扩展模块 检测通不过的解决方法php.in中下面两行已经放开注释：extension=pdo.soextension=pdo_mysql.soPDO检测仍然通不过。终极解决方案：php编译时加上如下参数，重新编...php.in中下面两行已经放开注释：
extension=pdo.so
extension=pdo...
How to flatten tree via LINQ?
...IEnumerable<MyNode> Flatten(IEnumerable<MyNode> e) =>
e.SelectMany(c => Flatten(c.Elements)).Concat(new[] { e });
You can then filter by group using Where(...).
To earn some "points for style", convert Flatten to an extension function in a static class.
public static IEnume...
How do SQL EXISTS statements work?
... criteria -- this is why it can be faster than IN. Also be aware that the SELECT clause in an EXISTS is ignored - IE:
SELECT s.*
FROM SUPPLIERS s
WHERE EXISTS (SELECT 1/0
FROM ORDERS o
WHERE o.supplier_id = s.supplier_id)
...should hit a division by zero error...