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SQL injection that gets around mysql_real_escape_string()
...ollowing query:
$iId = mysql_real_escape_string("1 OR 1=1");
$sSql = "SELECT * FROM table WHERE id = $iId";
mysql_real_escape_string() will not protect you against this.
The fact that you use single quotes (' ') around your variables inside your query is what protects you against this. The fo...
How to find elements by class
...
CSS selectors
single class first match
soup.select_one('.stylelistrow')
list of matches
soup.select('.stylelistrow')
compound class (i.e. AND another class)
soup.select_one('.stylelistrow.otherclassname')
soup.select('.st...
Replacement for “rename” in dplyr
...
The next version of dplyr will support an improved version of select that also incorporates renaming:
> mtcars2 <- select( mtcars, disp2 = disp )
> head( mtcars2 )
disp2
Mazda RX4 160
Mazda RX4 Wag 160
Datsun 710 108
Hornet 4 Drive 258
H...
LEFT JOIN only first row
...rtist_id) will be the earliest.
So try something like this (untested...)
SELECT *
FROM feeds f
LEFT JOIN artists a ON a.artist_id = (
SELECT
MIN(fa.artist_id) a_id
FROM feeds_artists fa
WHERE fa.feed_id = f.feed_id
) a
...
Swapping column values in MySQL
...rows affected (0.08 sec)
Records: 4 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM swaptest;
+------+------+
| X | Y |
+------+------+
| 1 | 2 |
| 3 | 4 |
| -5 | -8 |
| -13 | 27 |
+------+------+
4 rows in set (0.00 sec)
mysql>
Here is the swap being performed
m...
jQuery - selecting elements from inside a element
...
Actually, $('#id', this); would select #id at any descendant level, not just the immediate child. Try this instead:
$(this).children('#id');
or
$("#foo > #moo")
or
$("#foo > span")
...
What is the difference between JOIN and UNION?
...t -- completely different operations. Trivial example of UNION:
mysql> SELECT 23 AS bah
-> UNION
-> SELECT 45 AS bah;
+-----+
| bah |
+-----+
| 23 |
| 45 |
+-----+
2 rows in set (0.00 sec)
similary trivial example of JOIN:
mysql> SELECT * FROM
-> (SELECT 23 AS bah...
How to get a list of user accounts using the command line in MySQL?
...
Use this query:
SELECT User FROM mysql.user;
Which will output a table like this:
+-------+
| User |
+-------+
| root |
+-------+
| user2 |
+-------+
As Matthew Scharley points out in the comments on this answer, you can group by the ...
How do I use ROW_NUMBER()?
...
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...
MySQL DISTINCT on a GROUP_CONCAT()
I am doing SELECT GROUP_CONCAT(categories SEPARATOR ' ') FROM table . Sample data below:
6 Answers
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