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SQL UPDATE all values in a field with appended string CONCAT not working
...
That's pretty much all you need:
mysql> select * from t;
+------+-------+
| id | data |
+------+-------+
| 1 | max |
| 2 | linda |
| 3 | sam |
| 4 | henry |
+------+-------+
4 rows in set (0.02 sec)
mysql> update t set data=concat(data, 'a');...
Chaining multiple filter() in Django, is this a bug?
...estricted the set of blogs further to those that are also (B). The entries select by the second filter may or may not be the same as the entries in the first filter.`
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Update or Insert (multiple rows and columns) from subquery in PostgreSQL
...table.col1 = 123;
For the INSERT
Use:
INSERT INTO table1 (col1, col2)
SELECT col1, col2
FROM othertable
You don't need the VALUES syntax if you are using a SELECT to populate the INSERT values.
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How to get element by innerText
... This should be the top answer. XPath can do much more, like select node by attribute value, select node sets ... Simple intro: w3schools.com/xml/xpath_syntax.asp
– Timathon
Dec 2 '17 at 2:43
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How to pull a random record using Django's ORM?
...on't know about other databases).
order_by('?')[:N] will be translated to SELECT ... FROM ... WHERE ... ORDER BY RAND() LIMIT N query.
It means that for every row in table the RAND() function will be executed, then the whole table will be sorted according to value of this function and then first N...
How to get the system uptime in Windows? [closed]
...can also click CTRL+SHIFT+ESC to get to the Task Manager.
In Task Manager, select the Performance tab.
The current system uptime is shown under System or Performance ⇒ CPU for Win 8/10.
2: By using the System Information Utility
The systeminfo command line utility checks and displays various ...
Change C++/CLI project to another framework than 4.0 with vs2010
... the Platform Toolset setting in the General property page. You must then select "v90" to get a proper build that targets 3.5. It is however clumsy, you must have all intermediate versions of VS installed on the machine to have that selection available.
Why you need VS2008 installed requires an e...
Use '=' or LIKE to compare strings in SQL?
...
To see the performance difference, try this:
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name = B.name
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name LIKE B.name
Comparing strings with '=' is muc...
SQL Server 2008 can't login with newly created user
...ick on SQL Server instance at root of Object Explorer, click on Properties
Select Security from the left pane.
Select the SQL Server and Windows Authentication mode radio button, and click OK.
Right-click on the SQL Server instance, select Restart (alternatively, open up Services and restart the ...
How can I clone an SQL Server database on the same server in SQL Server 2008 Express?
...is optional.
Click to clone database and open restore dialog (see image)
Select Device and add the backup file from step 3.
Change destination to test database
Change location of database files, it must be different from the original. You can type directly into text box, just add postfix. (NOTE:...