Know About SQL

SQL seems to be the same basic concept in case you are familiar with databases. But let us make it more generic and view from the perspective of a layman who has no idea of any database. SQL is the short form of Structured. SQL statements have a special format defined. It has some special terms and conditions of tags that are arranged in a certain order.

Why SQL is required to be structured. Digging up the necessary information, we often ask questions or inquiries, and expect answers in the form of some decent data. SQL shares the same manner as a query that returns the data relevant and accurate. Language keyword is to respond to SQL in a way that other technical methods of standard script to follow certain predefined specifications.

Data can be stored in simple text files, Excel spreadsheets or databases. management systems, databases or database such as Microsoft Access are data containers in an organized manner. The data are organized in tables. The tables have rows and columns. Each attribute value is stored in these columns resulting in the lines.

These lines represent register. When a certain relationship is created between the tables, the database is called relational database relational databases (RDBMS) such as Microsoft SQL Server 2000. When a database is also concerned with objects, called DBMS object / relational (RDBMS) like Oracle. SQL acts as a tool to interact with these databases to different levels of data units.

With SQL, we can add new information needed to plan. SQL can also help us to manage and manipulate data. You can delete or modify rows in the record. And possible to delete an entire table or other parts of the database. It can also create a new table and its related objects. This indicates that the SQL may contain information and the database structure to lock. Can help manage and control a system database. Many users access the database. You can set permissions, permits and privileges limited, we can help SQL functionality.

The original version of SQL is designed to support only a simple database. But with the advent of new advanced features of databases of different software vendors had begun its own modified version of SQL database management system. Each version of the database, and new features were added to SQL statements. Some of them had expired. Compared to the original version, the latest version of SQL is more efficient and fast. It can handle a huge amount of information.

The examination has been reduced. Automatic scheduling of batch jobs and processes are common today. Notification and Reporting Services is integrated with a number of database servers like MS SQL Server 2008. Together with the SQL statements, the database also includes scripting code that can handle data transfer between the source and target different databases and servers. Therefore, SQL has a key role in almost every stage of processing.

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What is SPF (Sender Policy Framework) text record?

SPF – Sender Policy Framework. SPF is a TXT Record with some text in it. Usually SPF looks like this:
v=spf1 mx ~all, the meaning of tags you can see at Since it’s just a TXT record and publicly available, it was created for Anti-Spam software to be used. If a domain doesn’t have this record, and you send an email from this domain, most likely your email will go into SPAM/Junk folder and not inbox. Basically there are more and more features being invented to prevent spam senders and this one helps a little prove that the domain you are sending emails from is yours. It became so popular that now, other than TXT record, there is a special SPF record on DNS. We don’t create it for all clients. Nowadays mostly all spammers found a way to go around SPF anyway, so there are more things being created to prove that YOU were the sender of the email and not spammer. One of the new things is DKIM…to-SmarterMail used via TXT record too, but rather than just plain text like SPF, DKIM is encrypted, hashed and looks like this:

What is DNS text record (TXT) and its purpose?

It’s like a public notepad for each domain on DNS. Public is because it’s publicly available what’s written in DNS for this domain. Different companies and services can use TXT record for their purposes. TXT record doesn’t affect the domain’s availability (A record) or email availability (MX record). TXT record is really like a public notepad. One of the purposes often TXT record used is to identify that a client owns the domain. For us, it’s easy we can access account and dns ourselves, but what if a 3rd party company wants to know if this domain is YOURS. They provide some code and ask you to create a TXT record on your domain and put this code (or any text) in there. Once you added the text, they can read it off because it’s public information. This proves you have access to the domain’s dns and most likely own or manage the domain. Second most popular use for TXT is SPF.

Static IP vs Dedicated IP

There has been a lot of confusion between static and dedicated IP addresses. Today I would like to discuss this issue.

There are two types of IP addresses Dynamic and Static. Dynamic is the IP address that everyone receives automatically via DHCP server on home routers, wifi hot spots, etc. Basically anywhere you connect wirelessly or via cable and get internet connection automatically you get a dynamic IP address. Dynamic IP address can change when you connect next time. Servers cannot work with random IP addresses changes so we configure Static IP address on each server. So ALL servers have static IP addresses at all times. Static IPs cannot change randomly and assigned on a network card of each server. There can be more than one static IP address assigned to same server.

Shared Web Servers usually have a few IP addresses. By default all domains are assigned to just one IP address and all clients share this one IP address which makes this IP address a Shared IP. Technically it is possible to assign many domains to same IP address via binding in Internet Information Services (IIS7) and host headers in IIS6. Once a client wants to assign a SSL Certificate to his/her domain, shared binding/host headers are not possible anymore, so there is a requirement for a Dedicated IP. Once a dedicated IP is assigned to client’s domain, he/she is able to assign a SSL Certificate. The IP is now Dedicated to the client’s domain. The domain is no longer on a Shared IP address. Both Shared and Dedicated IP addresses are Static.

So it is incorrect to request a Static IP address from a web hosting company because all IP addresses are always static on all servers. Clients need to request a Dedicated IP address.

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