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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
...dn't want the overhead of a function. I came up with the following query:
SELECT myfield::integer FROM mytable WHERE myfield ~ E'^\\d+$';
Postgres shortcuts its conditionals, so you shouldn't get any non-integers hitting your ::integer cast. It also handles NULL values (they won't match the regex...
How to write a foreach in SQL Server?
... the lines of a for-each, where I would like to take the Ids of a returned select statement and use each of them.
10 Answer...
What is the simplest SQL Query to find the second largest value?
...
SELECT MAX( col )
FROM table
WHERE col < ( SELECT MAX( col )
FROM table )
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Pipe to/from the clipboard in Bash script
...lets you talk to it.
In the case of X, there's xclip (and others). xclip -selection c will send data to the clipboard that works with Ctrl + C, Ctrl + V in most applications.
If you're on Mac OS X, there's pbcopy. e.g cat example.txt | pbcopy
If you're in Linux terminal mode (no X) then look into...
jQuery: Select data attributes that aren't empty?
I'm trying to select all elements that have a data-go-to attribute that is not empty.
11 Answers
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How do I use ROW_NUMBER()?
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For the first question, why not just use?
SELECT COUNT(*) FROM myTable
to get the count.
And for the second question, the primary key of the row is what should be used to identify a particular row. Don't try and use the row number for that.
If you returned Ro...
using href links inside tag
...
<select name="forma" onchange="location = this.value;">
<option value="Home.php">Home</option>
<option value="Contact.php">Contact</option>
<option value="Sitemap.php">Sitemap</option>...
How to use OpenFileDialog to select a folder?
How to use OpenFileDialog to select folders?
8 Answers
8
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How do I select an entire row which has the largest ID in the table?
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You could use a subselect:
SELECT row
FROM table
WHERE id=(
SELECT max(id) FROM table
)
Note that if the value of max(id) is not unique, multiple rows are returned.
If you only want one such row, use @MichaelMior's answer,
SELEC...
How to create a listbox in HTML without allowing multiple selection?
...eate a simple listbox, but one of the requirements is to DISALLOW multiple selection. Most of the code for listboxes goes like this -
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