dba

How to recover the sa user password in Sql Server 2008

8

There are many ways to link it with our SqlServer database and one of them is to forget or not to have the user's password available to us. It may be because we never use it, because we have our own admin user and we really do not log in with that account. We may have inherited that wonderful database and we do not have any user or domain that is an administrator.

Defragment to optimize MySQL tables

4

 

In MySQL, when you delete records from a table, space is reallocated automatically. It is as empty space and forming new attachments will advantage.

The problem is that if a table perform many DELETE operations, the physical space of the table will become increasingly fragmented and the performance is reduced.

In the MyISAM and InnoDB, OPTIMIZE TABLE command available to perform an optimization on any table that, among other things, performs an automatic defragmentation of the table.

It is highly recommended to use this command regularly especially on tables that are more statements of disposal of records.

As a precaution, keep in mind that during implementation, of course, the table is blocked. You have to remember when you are going to use with large tables and busy.

Supersimples The syntax is:

 

OPTIMIZE [NO_WRITE_TO_BINLOG | LOCAL] TABLE mi_tabla1 [, mi_tabla2] ...;

To make a fragmented table optimization can be selected to have free space, probably as a result of DELETE statements:

Improve MySQL performance by adjusting some parameters

5.6

MySQL, like most database managers, can easily modify the parameters that control memory sizes engaged in certain tasks, resource utilization, concurrency limits, etc.

Properly adjusting these parameters can be obtained many performance improvements, especially if the server / s of the database is not about resources, and if the SQL optimization can not be improved more.

I've recently made some basic settings in a MySQL database, so I take this opportunity to explain some of the process I followed for those who seek an easy way to make a first optimization of parameters in the database. This is not to say that this is the best way to do just that to me has worked out well;)

The first comment that can be very helpful to look in phpMyAdmin to the sections 'Show information about MySQL runtime' and 'Show MySQL system variables', normally accessible from the home page of the application.

The first displays information and statistics collected and maintained the system since its beginning. Pay special attention to the values of variables that are displayed in red, and the advice provided to the right of these values.

Please refer to the variables used to determine the current values of the parameters that could later be modified to improve performance.

 

Easily export data from Oracle to flat file

6

A simple way to export data from a query, table, etc.. of an oracle database to a flat file is to use the SPOOL command in SQLPlus. This would not need to rely on visual aids, which are not always available or do not always work as we want. Also you can use the Oracle format functions in the same SELECT statement that generated the data already in the format we need.

If, for example, we want to retrieve some data from all records in a table of customers sorted by date of discharge, simply open a SQLPlus session and run this series of commands: 


SQL> SET HEADING OFF
SQL> SET FEEDBACK OFF
SQL> SPOOL C:\datos_de_clientes.txt
SQL> SELECT 'Cliente ' || CLI_NOMBRE || ', ' || CLI_NIF || '. Fecha alta: ' || TO_CHAR(CLI_FECHAALTA,'YYYY-MM-DD')
FROM TABLA_CLIENTES
ORDER BY CLI_FECHAALTA DESC;
SQL> SPOOL OFF;
SQL> SET FEEDBACK ON
SQL> SET HEADING ON

The first lines hide the headers that contain the field name, and do not concern us because we only want the data. Spool directs the output of data to the file 'datos_de_clientes.txt' on the C drive on the local machine.

Syndicate content