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Best way to check for “empty or null value”
... '
Demo
Empty string equals any string of spaces when cast to char(n):
SELECT ''::char(5) = ''::char(5) AS eq1
, ''::char(5) = ' '::char(5) AS eq2
, ''::char(5) = ' '::char(5) AS eq3;
Result:
eq1 | eq2 | eq3
----+-----+----
t | t | t
Test for "null or empty string" w...
Missing Push Notification Entitlement
...from the answer given by @Vaiden, in Xcode 8 you can resolve this issue by selecting the target and clicking the "Fix issue". Of course, you'll still need to set up push notifications in the Apple Developer portal (you can simplify the process a little by using the new "Automatically manage signing"...
How to enable MySQL Query Log?
...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 the cell highlight color of UITableView
I want to remove the default blue color of uitableview cell selection. I don't want any selection color there. I have not created a custom cell class. I'm customizing the cell by adding labels and buttons over it.
I tried doing:
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Update multiple rows in same query using PostgreSQL
...;
-- populate table with dummy rows
insert into results_dummy
(id, status)
select unnest(array[1,2,3,4,5]::int[]) as id, unnest(array['a','b','c','d','e']::text[]) as status;
select * from results_dummy;
-- THE update of multiple rows with/by different values
update results_dummy as rd
set stat...
How to store int[] array in application Settings
... int[] type by default in the settings file - it just doesn't allow you to select it by default.
So, create a setting with desired name (e.g. SomeTestSetting) and make it of any type (e.g. string by default).
Save the changes.
Now go to your project folder and open the "Properties\Settings.settings...
What is the fastest method for selecting descendant elements in jQuery?
As far is I know, there are a number of ways of selecting child elements in jQuery .
3 Answers
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How to turn IDENTITY_INSERT on and off using SQL Server 2008?
...
Import:
You must write columns in INSERT statement
INSERT INTO TABLE
SELECT * FROM
Is not correct.
Insert into Table(Field1,...)
Select (Field1,...) from TABLE
Is correct
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Eclipse HotKey: how to switch between tabs?
... in browser or window in operating system ( Cmd / Win + Tab ) without file-selection from the list. How to do this easy thing in Eclipse?
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Using Chrome, how to find to which events are bound to an element
...e Event you need
From the handler property, right click over function and select 'Show function definition'
You will now see the Event binding code
Click on the 'Pretty print' button for a more readable view of the code
sh...