About SQL
Structured Query Language (SQL) is a well-known programming language that provides database developers, administrators, and users with the ability to manage, modify, and retrieve data from relational databases. Its simplicity has made it the industry standard on which well-known database management systems such as MySQL, Oracle, Microsoft SQL Server, and PostgreSQL are based. SQL allows database specialists to perform a variety of tasks, including adding, modifying, and deleting data, creating and modifying database tables, enforcing data integrity, and generating reports. Basically, SQL is an indispensable tool for anyone who wants to perform database operations efficiently. The role of databases in modern information technology is truly indispensable. Databases contain functional and pertinent information that is essential for the smooth operation of businesses in various industries. Developing and managing databases can be a difficult and technical process that requires skill and expertise. Fortunately, developers and database administrators can leverage the power of structured query language (SQL) to interact with databases, accurately retrieve the data they need, and organize it in a logical way that makes sense for specific business needs. SQL is an efficient tool that enables seamless communication between databases and the stakeholders that rely on them.
Advantage of SQL
1) Faster and Efficient Query Processing.
Using SQL queries, a lot of data from the database may be accessed fast and effectively. Additionally, the time needed to execute data insertion, deletion, and updating tasks is decreased.
2)No Need for Coding Skills
For administering database systems, SQL doesn't need a lot of lines of code. Using straightforward SQL syntactical principles, the database may be accessed and maintained with ease. SQL is user-friendly because of these basic guidelines.
3)Portable
Desktops, laptops, tablets, and even smartphones can all use the structured query language with ease. Depending on what the user needs, it can also be utilized with other programs.
4)Standardized Language
SQL adheres to the enduring standards of ISO and ANSI, which provide a uniform platform to all of its users around the world.
5)Interactive Language
It's easy to understand and learn the SQL language. This language is a straightforward query language, therefore we can use it for database communication as well. The answers to difficult inquiries can also be quickly obtained using this language.
6)Multiple Data Views
Additionally, the SQL language aids in creating various views of the database structure for various database users.
Structured Query Language (SQL) was first developed in the early 1970s by IBM researchers Donald Chamberlin and Raymond Boyce. Their goal was to create a language that could manipulate and retrieve data stored in a database management system. Their initial design, called SEQUEL (Structured English Query Language), used English-like commands to interact with the database. In 1974, IBM released a prototype implementation of SEQUEL on its System R database system, which was used to demonstrate the language's capabilities. However, due to copyright issues with the name SEQUEL, the language was renamed SQL.
PROCESS OF SQL
Whenever we run a SQL command on a relational database management system, the system will automatically select the appropriate procedure to carry out our request, and the SQL engine will decide how to interpret that specific instruction.
Built-in Query The following four elements make up language throughout its process.
HOW TO CREATE A DATABASE?
syntax:-
syntax:-
HOW TO INSERT VALUES IN TABLES?
syntax:-
In SQL, a datatype is a specific type of data that can be stored in a database table or column. Different datatypes are used for different types of data, such as numbers, text, dates, and times. Here are some common datatypes in SQL:- INTEGER - used to store whole numbers, such as 1, 2, 3, etc.
- FLOAT - used to store floating-point numbers, such as 3.14, 2.718, etc.
- DECIMAL - used to store exact numeric values with a specified precision and scale, such as 12.345.
- CHAR - used to store fixed-length strings of characters, such as 'Hello'.
- VARCHAR - used to store variable-length strings of characters, such as 'World'.
- DATE - used to store dates in the format YYYY-MM-DD.
- TIME - used to store times in the format HH:MM:SS.
- TIMESTAMP - used to store dates and times in the format YYYY-MM-DD HH:MM:SS.
- BOOLEAN - used to store true/false values.
- BLOB - used to store binary data, such as images or documents.
Note-It is important to choose the appropriate datatype for each column in a database table to ensure that the data is stored efficiently and accurately. Using the wrong datatype can result in wasted storage space or incorrect data values. Additionally, some databases have specific datatypes that are unique to that database system, so it is important to consult the database documentation for a complete list of available datatypes.
OPERATORS IN SQL
In SQL, operators are used to performing various operations on data, such as comparisons, arithmetic calculations, and logical operations. Here are some common operators in SQL:
1)Comparison operators:
- >= (greater than or equal to)
- <= (less than or equal to)
These operators are used to compare values and return true or false based on the comparison result.
2)Arithmetic operators:
These operators are used to perform arithmetic calculations on numeric values.
3)Logical operators:These operators are used to combine multiple conditions and return true or false based on the logical result.
4)String operators:
This operator is used to concatenate two or more strings together.
5)Bitwise operators:
It is important to use operators correctly and in the appropriate context to ensure that queries return accurate and useful results. In addition to the operators listed above, there may be additional operators specific to certain databases or programming languages. It is important to consult the appropriate documentation for a complete list of available operators.
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