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Missing file warnings showing up after upgrade to Xcode 4
...Code 4.2.+ (possibly in 4+) you can avoid manual work and command line :
Select project Project Navigator (Command - 1)
Choose File - Source Control - Commit menu
In the left pane, on top of it you have three icons, select the middle one - File view
You will see the list of all missing files
Selec...
Show constraints on tables command
...
Simply query the INFORMATION_SCHEMA:
USE INFORMATION_SCHEMA;
SELECT TABLE_NAME,
COLUMN_NAME,
CONSTRAINT_NAME,
REFERENCED_TABLE_NAME,
REFERENCED_COLUMN_NAME
FROM KEY_COLUMN_USAGE
WHERE TABLE_SCHEMA = "<your_database_name>"
AND TABLE_NAME = "<y...
What does SQL clause “GROUP BY 1” mean?
...
SELECT account_id, open_emp_id
^^^^ ^^^^
1 2
FROM account
GROUP BY 1;
In above query GROUP BY 1 refers to the first column in select statement which is
account_id.
You also can speci...
Copy existing project with a new name in Android Studio
...
I've selected the base package folder and clicked Refactor -> Rename, I got errors with "package rename" option, then I did "folder rename" option with success.
– Ismail Yavuz
May 23 '19 a...
Difference between “change” and “input” event for an `input` element
...an element is changed through the user interface.
onchange occurs when the selection, the checked state or the contents of an element have changed. In some cases, it only occurs when the element loses the focus or when pressing return (Enter) and the value has been changed. The onchange attribute ca...
MySQL CONCAT returns NULL if any field contain NULL
...
convert the NULL values with empty string by wrapping it in COALESCE
SELECT CONCAT(COALESCE(`affiliate_name`,''),'-',COALESCE(`model`,''),'-',COALESCE(`ip`,''),'-',COALESCE(`os_type`,''),'-',COALESCE(`os_version`,'')) AS device_name
FROM devices
...
SQL Server Installation - What is the Installation Media Folder?
... Server 2019 Developer version. Was lost with dialog prompted from step 3 "Select installation media". This Andy Leonard blog helped me: 1. Downloaded installation package from SQL Server downloads. 2. Launch downloaded wizard > Select installation type > Download media 3. Right-click on the d...
Multiline strings in VB.NET
...
I used this variant:
Dim query As String = <![CDATA[
SELECT
a.QuestionID
FROM
CR_Answers a
INNER JOIN
CR_Class c ON c.ClassID = a.ClassID
INNER JOIN
CR_Questions q ON q.QuestionID = a.QuestionID
...
Angular ng-repeat Error “Duplicates in a repeater are not allowed.”
...cause I mistakenly set the ng-model the same as the ng-repeat array:
<select ng-model="list_views">
<option ng-selected="{{view == config.list_view}}"
ng-repeat="view in list_views"
value="{{view}}">
{{view}}
</option>
</select>
Inste...
How do I find which transaction is causing a “Waiting for table metadata lock” state?
...about all the locks transactions are waiting for:
USE INFORMATION_SCHEMA;
SELECT * FROM INNODB_LOCK_WAITS;
A list of blocking transactions:
SELECT *
FROM INNODB_LOCKS
WHERE LOCK_TRX_ID IN (SELECT BLOCKING_TRX_ID FROM INNODB_LOCK_WAITS);
OR
SELECT INNODB_LOCKS.*
FROM INNODB_LOCKS
JOIN INNOD...