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How do you create a read-only user in PostgreSQL?
I'd like to create a user in PostgreSQL that can only do SELECTs from a particular database. In MySQL the command would be:
...
jQuery remove options from select
I have a page with 5 selects that all have a class name 'ct'. I need to remove the option with a value of 'X' from each select while running an onclick event. My code is:
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SQL select only rows with max value on a column [duplicate]
...ce...
All you need is a GROUP BY clause with the MAX aggregate function:
SELECT id, MAX(rev)
FROM YourTable
GROUP BY id
It's never that simple, is it?
I just noticed you need the content column as well.
This is a very common question in SQL: find the whole data for the row with some max value ...
Get the Highlighted/Selected text
...
Getting the text the user has selected is relatively simple. There's no benefit to be gained by involving jQuery since you need nothing other than the window and document objects.
function getSelectionText() {
var text = "";
if (window.getSelecti...
Remove an entire column from a data.frame in R
...=4:6)
to remove just the a column you could do
Data <- subset( Data, select = -a )
and to remove the b and d columns you could do
Data <- subset( Data, select = -c(d, b ) )
You can remove all columns between d and b with:
Data <- subset( Data, select = -c( d : b )
As I said above...
Adding 'serial' to existing column in Postgres
...int, b text);
CREATE TABLE bar (a serial, b text);
INSERT INTO foo (a, b) SELECT i, 'foo ' || i::text FROM generate_series(1, 5) i;
INSERT INTO bar (b) SELECT 'bar ' || i::text FROM generate_series(1, 5) i;
-- blocks of commands to turn foo into bar
CREATE SEQUENCE foo_a_seq;
ALTER TABLE foo ALTER...
How do I replace text in a selection?
...e you have open.
There is an icon option which when hovered over says "In Selection" that you can select to find and replace within a selection. I've pointed to the correct icon in the screenshot below.
Hit replace all, and voila, all instances of '0' will be replaced with '255'.
Note: this ...
Reset select2 value and show placeholder
How do I set the placeholder on value reset by select2. In my example If locations or grade select boxes are clicked and my select2 has a value than the value of select2 should reset and show the default placeholder. This script is resetting the value but won't show the placeholder
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MySQL Error 1093 - Can't specify target table for update in FROM clause
...s question
In MySQL, you can't modify the same table which you use in the SELECT part.
This behaviour is documented at:
http://dev.mysql.com/doc/refman/5.6/en/update.html
Maybe you can just join the table to itself
If the logic is simple enough to re-shape the query, lose the subquery and join th...
Set cursor position on contentEditable
...upport DOM Range.
var editable = document.getElementById('editable'),
selection, range;
// Populates selection and range variables
var captureSelection = function(e) {
// Don't capture selection outside editable region
var isOrContainsAnchor = false,
isOrContainsFocus = false,
...