Posts

Create a table like another table or from a select query

There are some cases where we need to create a table similar or exactly same as another table. The easiest and best way is use create table along with additional parameters. We can create a table similar to another table without data and with data. Creat …

Installing Django on Dreamhost

Installing Django in Dreamhost and getting it to run wasn’t straight forward at-least to me. There was lot of issues such as python bin directory not accessible as its shared and so. So the initial step in this to setup python yourself so that you can use …

Customizing Mysql Prompt For multiple Servers

If you are using mysql regularly on multiple servers its really useful to have the promt in mysql to show something more than mysql>. It would be useful if it showed the username,hostname, current database and things like that. So how to do this. One m …

Group by Date when Stored in Mysql DataBase as Date Time

I have a table called date_count with 2 columns one is a value and another is a date time, say called date_time in mysql. Date Time in mysql is stored as dd-mm-yy hh:mm:ss. The issue comes when I need to get the number of rows per day. As its stored as dat …

Check if a table exists in MySQL from PHP

Sometimes its necessary to execute a query or execute some code if a table exists or not. So a bit of searching got me to the conclusion that mysql doesn’t have a direct query or method for it from php. So there are two methods to do it. Use the mysql c …

Get the nth Word from a text field in mysql

I had a requirement to get the nth word out of a string and sort or order by the same. This is used when the text is stored in a purticular format and you would want to order it according to that or group it or so on. So how is it done? We do it using a  …

Important MySQL DBA Interview Questions

Here are a few sets of interview questions expected for MySQL DBA position.These are compilation of the usual questions from various DBA texts: What is Log Switch? – The point at which ORACLE ends writing to one online redo log file and begins writing to …

User Level Threads

User level threads is created for light weight threads. It needs to be controlled, context switched and swapped by the process. To the Operating System it is only one process without any threads. Here is one implementation of it: q.h





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Check the port in which the Mysql is running on

Mysql can be configured to run other ports other than the default port (of 3306). So what will you do when you need to find the port on which a mysql server runs on. If you don’t have access to the server files and can access the server only using the mysq …

Generate Date from a range in Mysql and pad the results where no date is present

If you want to generate dates, MYSQL doesn’t have a range function, so I wrote a work around for the same. So how¬† it works is I have reused a code to generate numbers from my previous post. So I added date function to that query and reduce the generated  …