How 2 Guru

Today I would like to share some useful command for developer to export out data by using SQL statement.
I think most of the developer should familiar with the putty & command line environment.
But always facing an problem to export out the data in a excel/csv file in order to send it to customer.

Here is a simple but useful MySQL command to export out your data in a csv file.
read more »

When perform some data clean up in MySQL, found that no disk space was release and MySQL still occupied it.

Here is the command to check those tables with more than 300MB of data:
read more »

How to check MySQL database size in your server? 
Actually MySQL already provide the information, what you need to do is just do a simple query to retrieve the data.

Below is the query :

read more »

Recently I am trying to dump a customer MySQL database to a SQL file & restore to another server.
An error occur during the dump process.

The error mention that one of the table in the database is crashed & repair required.
Then I try to login into MySQL server & use the particular database & execute the “DESC” command.
The result is “ERROR 145 (HY000): Table ‘./XXXXXXX/tracker’ is marked as crashed and should be repaired”

mysql> desc tracker;
ERROR 145 (HY000): Table './XXXXXXX/tracker' is marked as crashed and should be repaired
mysql> check table tracker;
+----------------------+-------+----------+----------------------------------------------------------------------------+
| Table                | Op    | Msg_type | Msg_text                                                                   |
+----------------------+-------+----------+----------------------------------------------------------------------------+
| XXXXXXX.tracker      | check | error    | Table './XXXXXXXXX/tracker' is marked as crashed and should be repaired |
+----------------------+-------+----------+----------------------------------------------------------------------------+
1 row in set (0.03 sec)

read more »

Today I am trying to restore one of MySQL dump into my development database.
While I executing the mysql -uroot -p XXXX < XXXX.sql, the restoration show me the error of ”ERROR 2006 (HY000) at line 3051: MySQL server has gone away“.

Then I double check on the database that I restore, I found that the action terminated in the middle & some of the tables & data is not restored.

I googled a while & found the solution.

read more »