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MySQL Query GROUP BY day / month / year
... for added clarity in some cases such as where records span several years. SELECT COUNT(event_id), DATE_FORMAT(event_start, '%Y/%m')
– Ric
Apr 4 '13 at 10:25
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Hide options in a select list using jQuery
...ave an object with key/value pairs of options I want to hide/remove from a select list.
Neither of the following option selectors work. What am I missing?
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How to generate the “create table” sql statement for an existing table in postgreSQL
... text;
column_record record;
BEGIN
FOR column_record IN
SELECT
b.nspname as schema_name,
b.relname as table_name,
a.attname as column_name,
pg_catalog.format_type(a.atttypid, a.atttypmod) as column_type,
CASE WHEN
...
How to resolve symbolic links in a shell script
...andards, pwd -P should return the path with symlinks resolved.
C function char *getcwd(char *buf, size_t size) from unistd.h should have the same behaviour.
getcwd
pwd
share
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improve this answer
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UPDATE multiple tables in MySQL using LEFT JOIN
...= t1.id
SET t1.col1 = newvalue
WHERE t2.id IS NULL
Note that for a SELECT it would be more efficient to use NOT IN / NOT EXISTS syntax:
SELECT t1.*
FROM t1
WHERE t1.id NOT IN
(
SELECT id
FROM t2
)
See the article in my blog for performance details...
Remove all classes that begin with a certain string
...
Careful with this one. Word boundary splits on dash character ('-') and dots and others, so class names like "bg.a", "bg-a" etc. will not be removed but replaced with ".a", "-a" etc. So if you have classnames with punctuation characters you may run into trouble by just running...
How to manually expand a special variable (ex: ~ tilde) in bash
...safer and better solutions. Preferably, I'd go with either of these two:
Charle's Duffy's solution
Håkon Hægland's solution
Original answer for historic purposes (but please don't use this)
If I'm not mistaken, "~" will not be expanded by a bash script in that manner because it is treated a...
Beautiful Soup and extracting a div and its contents by ID
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Beautiful Soup 4 supports most CSS selectors with the .select() method, therefore you can use an id selector such as:
soup.select('#articlebody')
If you need to specify the element's type, you can add a type selector before the id selector:
soup.select('di...
Difference between SelectedItem, SelectedValue and SelectedValuePath
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Their names can be a bit confusing :). Here's a summary:
The SelectedItem property returns the entire object that your list is bound to. So say you've bound a list to a collection of Category objects (with each Category object having Name and ID properties). eg. ObservableCollection&l...
Is it possible to GROUP BY multiple columns using MySQL?
Is it possible to GROUP BY more than one column in a MySQL SELECT query? For example:
7 Answers
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