Think Lamp » MySQL

Multiple SQL Queries in a Stored Procedure.

admin — Thu, 18 Dec 2008 21:21:40 +0000

Working on a Thursday afternoon, I came across a problem where we had to return multiple counts (about 10 of them ) in an application. One way was to have multiple stored procedures and call them one by one, but this would mean I would have to make 10 connections to the database and 10 opens , 10 closes, phew !

So I decided to combine all of them into one:

SELECT "totaltrees" =(SELECT count(*) FROM Forest f WHERE f.trees= @forestId), "totalplants" =(SELECT count(*) FROM Forest f WHERE f.plants= @forestId), "totalUsers"=(SELECT count(*) FROM Users u WHERE u.groupId= @groupId)

Here you can add as many as queries you want and from different tables, counts, columns etc. Just one thing, The result of each query should have a unique value, thus you can’t do select * !!

Or something like: select country_name FROM world.

cool ! isn’t it ?

Pagination in mysql CLI

admin — Thu, 16 Oct 2008 19:01:30 +0000

Ever wonder how to scroll upwards in mysl resultset ?

What if your terminal doesn’t allow scrollback or the scrollback buffer is somehow set to sreen lines ?

How to use MORE or LESS unix commands in mysql which would allow to scroll using ‘return’ or ‘spacebar’

Follow the steps given below:

[Invoke mysql using the --page command]

```
mysql --page uuser -p  
```

[set the pager to use less]

```
mysql> pager less
```

[run your query]

```
mysql> select * from table_name
```

This also works under the unix ‘screen’ terminal emulation

Hello Lamp-World !

admin — Mon, 11 Aug 2008 04:16:01 +0000

Welcome to the world of LAMP.

For all you disgraceful people who don’t know what it is, the definition:

L = > Linux ( Its an operating system )
A => Apache ( Its a web server )
M => MySQL ( Its a database system )
P => PhP {&perl } ( These are programming languages )

Wiki page: http://en.wikipedia.org/wiki/LAMP_(software_bundle)

We, here, at Lamp-World are group of people who live eat and think lamp. This site is aimed to have a collection of amazing ‘scripts’ , ‘tweaks’ and ‘solutions’ which you may not find anywhere else.