This statement can be used with INSERT, DELETE, SELECT, UPDATE and REPLACE statements. The EXPLAIN and DESCRIBE statements are synonyms used to obtain a query execution plan and the information about a table structure respectively. So, once you use this command, your information will be lost, but not the table will still be present in the database. The TRUNCATE statement is used to delete the information present in the table, but not the table itself. Add a column DOB and change the data type from Date to Year. Apart from this, you can also ALTER/MODIFY a specific column. You can use ALTER TABLE with ADD/ DROP column to either add or drop a column in the table. The ALTER statement is used to delete, add, modify columns in an existing table. ![]() The ALTER statement is used to add, delete or modify constraints or columns in an existing table. When you use this statement, complete information present in the view will be lost. When you use this statement, complete information present in the table will be lost. When you use this statement, complete information present in the database will be lost. The DROP statement is used to drop an existing table, view or a database. Note: Before you start creating a table and entering values, you have to use the database, using the USE statement as This statement is used to create a table. The CREATE statement is used to create a table, view or a database in the following way: CREATE DATABASE In this SQL tutorial, I am going to consider the below database as an example, to show you how to write queries using these SQL commands. In this article on SQL tutorial, we are going to discuss the following statements: SQL consists of various commands or statements to add, modify, delete or update data in the database. Immerse yourself in the world of NoSQL databases with our MongoDB Certification. So, now that you know what is SQL and its’ basics, let us understand the top commands or statements in SQL. To know the different operators supported by SQL, in an elaborated manner, you can click here. SQL supports the following types of Operators: Consider the expression 4 + 6 = 10, here 4 and 6 are operands and + is called operator. Operators are the constructs which can manipulate the values of the operands. If you wish to get a detailed understanding of the different SQL data types, you can refer to detailed guide on SQL Data Types. Other – This section of data types has data types such as table, XML, cursor, uniqueidentifier, and sql_variant.Date & Time – T his data type allows data to be stored in different formats of date and time.Binary – The Binary data types allows data to be stored in the format of binary values, for fixed and variable length.This data type also can be further categorized into Unicode characters, which allow fixed and variable length of Unicode characters. Character String – This data type allows characters of fixed and variable length. ![]() They can be further divided into exact and approximate data types where exact allows the integers in the form of whole numbers and approximate allow floating integers. Numeric – The numeric data types allow both signed and unsigned integers.SQL Data Types are divided into the following categories: Now that you know the basics of SQL, next in this SQL tutorial, let us understand what are the different SQL Data Types. SQL allows you to embed within other languages using SQL libraries and modules.With SQL, you can set permissions on tables, views, and procedures and grant specific permissions to different users.SQL allows the users to access, modify, and describe data in RDBMS.It allows the users to define and manipulate data in databases.With SQL, you can create and drop tables and databases. ![]() Also, relational databases like MySQL Databases, Oracle, MS SQL Server, Sybase etc use SQL to modify data. DDL, DML, DCL, and TCL to play with data in databases. SQL consists of various commands segregated into 4 categories i.e. SQL Tutorial: Introduction To SQL What is SQL?ĭeveloped by Donald D.Chamberlin in the 1970s, Structured Query Language or most commonly known as SQL is one of the most popular languages used to manipulate, store, update and retrieve data from a relational database. So, in this article on SQL Tutorial, I will discuss the following important concepts, which are a must to one’s journey on becoming a Database Administrator. Well, this is where Structured Query Language or SQL comes into the picture. In today’s market, where around 2.5 Quintillion bytes of data gets generated every day, it is very important to understand how to handle such a humongous amount of data.
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