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How do I get the last inserted ID of a MySQL table in PHP?
...TO_INCREMENT column by that client. This is the reason you should not use select MAX(ID)
– woens
Oct 4 '12 at 20:15
...
MySQL Server has gone away when importing large sql file
...r. To get their values, type in the mysql client:
> select @@wait_timeout;
> select @@max_allowed_packet;
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/usr/include/c++/4.9/bits/stl_iterator_base_types.h:165:53: error: ‘i...
..._iterator_base_types.h:165:53: error: ‘int’ is not a class, struct, or union type先看下面的代码(来自:SO)：#include <iostream>#include <cmath>#include <vector>using namespace std;double distance(int a, in...先看下面的代码(来自: SO)：
#include <iostream>
#include <cmath>
#...
How to move columns in a MySQL table?
...min provides a GUI for this within the structure view of a table.
Check to select the column you want to move and click the change action at the bottom of the column list.
You can then change all of the column properties and you'll find the 'move column' function at the far right of the screen.
Of ...
mysql - how many columns is too many?
...every column to be returned by every query is perfectly normal; that's why SELECT statement lets you explicitly name the columns you need.
As a general rule, your table structure should reflect your domain model; if you really do have 70 (100, what have you) attributes that belong to the same entit...
How to set initial value and auto increment in MySQL?
...r) values("kowalski's nuclear reactor.");
Step 4, interpret the output:
select * from penguins
prints:
'1001', 'We need more power!'
'1002', 'Time to fire up'
'1003', 'kowalski\'s nuclear reactor'
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#1071 - Specified key was too long; max key length is 1000 bytes
... the best prefix length for a given column? Here's a method to find out:
SELECT
ROUND(SUM(LENGTH(`menu_link`)<10)*100/COUNT(`menu_link`),2) AS pct_length_10,
ROUND(SUM(LENGTH(`menu_link`)<20)*100/COUNT(`menu_link`),2) AS pct_length_20,
ROUND(SUM(LENGTH(`menu_link`)<50)*100/COUNT(`menu_...
How to use Git properly with Xcode?
...add this line to a .gitattributes file:
*.pbxproj text -crlf -diff -merge=union
Then git will always take both sides of a merge for the .pbxproject files, having the same effect as the script I provided only without any extra work.
Lastly, here is my complete .gitignore file, showing what I do h...
MySQL IF NOT NULL, then display 1, else display 0
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SELECT c.name, IF(a.addressid IS NULL,0,1) AS addressexists
FROM customers c
LEFT JOIN addresses a ON c.customerid = a.customerid
WHERE customerid = 123
...
must appear in the GROUP BY clause or be used in an aggregate function
...
Yes, this is a common aggregation problem. Before SQL3 (1999), the selected fields must appear in the GROUP BY clause[*].
To workaround this issue, you must calculate the aggregate in a sub-query and then join it with itself to get the additional columns you'd need to show:
SELECT m.cname...