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How to check if field is null or empty in MySQL?
...
Either use
SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1
from tablename
or
SELECT case when field1 IS NULL or field1 = ''
then 'empty'
else field1
end as field1
from tablename
...
Install MySQL on Ubuntu without a password prompt
...
sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password password your_password'
sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password_again password your_password'
sudo apt-get -y install ...
How to implement custom JsonConverter in JSON.NET to deserialize a List of base class objects?
...o match a divierd class based on the class given to the serilaizer
/// Selected class will be the first class to match all properties in the json object.
/// </summary>
public class KnownTypeConverter : JsonConverter
{
public override bool CanConvert(Type objectType)
...
Return number of rows affected by UPDATE statements
...NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
DECLARE @RowCount1 INTEGER
DECLARE @RowCount2 INTEGER
DECLARE @RowCount3 INTEGER
DECLARE @RowCount4 INTEGER
UPDATE Table1 Set Column = 0 WHERE Column IS NULL
SEL...
Webstorm: “Cannot Resolve Directory”
...t directory as a Resource. To do this, go to Settings > Directories and select your asset root folder from the right-hand panel. Then mark it as Resource Root by clicking the button above the file browser.
From the Jetbrains documentation, a Resource Root enables WebStorm to complete relative pa...
How can I use Async with ForEach?
...ext db = new DataLayer.DataContext())
{
var tasks = db.Groups.ToList().Select(i => GetAdminsFromGroupAsync(i.Gid));
var results = await Task.WhenAll(tasks);
}
The benefits of this approach over giving an async delegate to ForEach are:
Error handling is more proper. Exceptions from asy...
How can I determine what font a browser is actually using to render some text?
...that, but Safari needs you to copy some text and investigate that.
First, select some text. In Firefox, the Page Inspector has a Fonts view:
This will also tell you if fonts were downloaded, and which style is used, such as Regular, ExtraLight, Italic, BoldItalic and all.
For Chrome, go into De...
“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...int, unique key (u));
mysql> insert into foo (u) values (10);
mysql> select * from foo;
+----+------+
| id | u |
+----+------+
| 1 | 10 |
+----+------+
mysql> show create table foo\G
CREATE TABLE `foo` (
`id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
`u` int(11) DEFAULT NULL,
...
Android Fatal signal 11 (SIGSEGV) at 0x636f7d89 (code=1). How can it be tracked down?
...y.
TODO:
A future version of ndk-stack will try to launch adb logcat and select the library path automatically. For now, you'll have to do these steps manually.
As of now, ndk-stack doesn't handle libraries that don't have debug information in them. It may be useful to try to detect the nearest f...
Git Extensions: Win32 error 487: Couldn't reserve space for cygwin's heap, Win32 error 0
...ck and load cmd.exe as admin, so I launched cmd.exe right click from start select start as admin, then cd into the directory, then run the command. It worked!
– edencorbin
Jan 5 '17 at 18:00
...