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What does it mean when a CSS rule is grayed out in Chrome's element inspector?
... because one or more rules from the set are being applied to the currently selected DOM node.
I guess, for the sake of completeness, dev tools shows all the rules from that set, whether they are applied or not.
In the case where a rule is applied to the currently selected element due to inheritance...
How to create a table from select query result in SQL Server 2008 [duplicate]
I want to create a table from select query result in SQL Server, I tried
6 Answers
6
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Firefox ignores option selected=“selected”
If you change a dropdown and refresh the page, Firefox seems to ignore the selected attribute.
20 Answers
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Finding duplicate values in MySQL
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Do a SELECT with a GROUP BY clause. Let's say name is the column you want to find duplicates in:
SELECT name, COUNT(*) c FROM table GROUP BY name HAVING c > 1;
This will return a result with the name value in the first colum...
How to best display in Terminal a MySQL SELECT returning too many fields?
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Terminate the query with \G in place of ;. For example:
SELECT * FROM sometable\G
This query displays the rows vertically, like this:
*************************** 1. row ***************************
Host: localhost
Db: mydatabase1
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ROW_NUMBER() in MySQL
...asy, but actually it kind of isn't).
I often plump for a null-self-join:
SELECT t0.col3
FROM table AS t0
LEFT JOIN table AS t1 ON t0.col1=t1.col1 AND t0.col2=t1.col2 AND t1.col3>t0.col3
WHERE t1.col1 IS NULL;
“Get the rows in the table for which no other row with matching col1,col2 has a hi...
How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
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@MichaelFirth "double inversion" !! is equivalent to casting something to a bool. Some people like to write it this way.
– Ben XO
Aug 6 '19 at 13:05
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How to disable GCC warnings for a few lines of code
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Another pattern is to just do a cast of the variable to void. In fact, I have seen in a project the following macro: #define UNUSED(x) ((void)x) used to silence warnings. I think it was in ReactOS?
– Paul Stelian
Apr 1...
How to list the tables in a SQLite database file that was opened with ATTACH?
...quently, if you used
ATTACH some_file.db AS my_db;
then you need to do
SELECT name FROM my_db.sqlite_master WHERE type='table';
Note that temporary tables don't show up with .tables either: you have to list sqlite_temp_master for that:
SELECT name FROM sqlite_temp_master WHERE type='table';
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Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
...irm this - I just updated a query with 4 joins on a 168,000 row database. Selecting just the first 100 rows with a SQL_CALC_FOUND_ROWS took over 20 seconds; using a separate COUNT(*) query took under 5 seconds (for both count + results queries).
– Sam Dufel
Ju...