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You can't specify target table for update in FROM clause
...llow you to write queries like this:
UPDATE myTable
SET myTable.A =
(
SELECT B
FROM myTable
INNER JOIN ...
)
That is, if you're doing an UPDATE/INSERT/DELETE on a table, you can't reference that table in an inner query (you can however reference a field from that outer table...)
Th...
sql query to return differences between two tables
...colum C, here are the records, which are present in table A but not in B:
SELECT A.*
FROM A
LEFT JOIN B ON (A.C = B.C)
WHERE B.C IS NULL
To get all the differences with a single query, a full join must be used, like this:
SELECT A.*, B.*
FROM A
FULL JOIN B ON (A.C = B.C)
WHERE A.C IS NUL...
Unknown Column In Where Clause
...om right to left. So the where clause is parsed and evaluate prior to the select clause. Because of this the aliasing of u_name to user_name has not yet occurred.
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Is the pImpl idiom really used in practice?
...about the implementation or just break the encapsulation by using terrible casting tricks. PIMPL solves/mitigates that.
Compilation time
Compilation time is decreased, since only the source (implementation) file of X needs to be rebuilt when you add/remove fields and/or methods to the XImpl class...
Why is Spring's ApplicationContext.getBean considered bad?
I asked a general Spring question: Auto-cast Spring Beans and had multiple people respond that calling Spring's ApplicationContext.getBean() should be avoided as much as possible. Why is that?
...
How do I disable text selection with CSS or JavaScript? [duplicate]
...
<div
style="-moz-user-select: none; -webkit-user-select: none; -ms-user-select:none; user-select:none;-o-user-select:none;"
unselectable="on"
onselectstart="return false;"
onmousedown="return false;">
Blabla
</div>
...
Macro vs Function in C
...ch as checking their type, sizeof, check struct members are present before casting(can be useful for polymorphic types).Or check an array meets some length condition.see: https://stackoverflow.com/a/29926435/432509
While its noted that functions do type checking, C will coerce values too (ints/float...
How to take MySQL database backup using MySQL Workbench?
...ble) within Server Administration.
Steps to Create New Server Instance:
Select New Server Instance option within Server Administrator.
Provide connection details.
After creating new server instance , it will be available in Server Administration list. Double click on Server instance you have cr...
Get selected option text with JavaScript
...
Try options
function myNewFunction(sel) {
alert(sel.options[sel.selectedIndex].text);
}
<select id="box1" onChange="myNewFunction(this);">
<option value="98">dog</option>
<option value="7122">cat</option>
<option value="142">bird</option&g...
SELECT INTO a table variable in T-SQL
Got a complex SELECT query, from which I would like to insert all rows into a table variable, but T-SQL doesn't allow it.
8...