WHERE is one of the major clauses of SQL and it is used to specify the conditions while retrieving the data from the single or multiple tables. The WHERE clause act like an IF statement of high-level programming languages and this often use when we want to access a specific data range or data from the tables. The… Read More »
In SQL when we want to see the data then we use the SQL SELECT command, the SELECT command work along with the FROM command and it fetch the data from the tables and return data in tabular form. SELECT-Syntax SELECT column_name_1, column_name_2, column_name_N FROM table_name; Example For instance, we have a Students table: +——+——–+——+——–+——-+ | id |… Read More »
Once we have created a table in database, now we can insert data in it, and the data store in the form of rows. To insert data in a table we use the SQL INSERT command. INSERT Data Syntax In SQL we have two possible methods to insert data in a table: In first way, when we insert… Read More »
If we do not require a table in a database then we can simply delete it by using the SQL DROP TABLE command. DROP TABLE comes very usefully when we especially want to delete the complete table, and while deleting a table make sure that you delete the correct one. Syntax Follow this syntax to delete a table… Read More »
After creating and selecting a database using CREATE and USE commands now we can create a table inside that database, and keep remember we can create more than one table in a single database. What is a Table in the Database? A table is a collection of rows and columns which form cells like structure and the data… Read More »
If we have multiple Databases in our SQL schema then in order to operate on specific database first, we need to select that it then only we are capable of using the queries on that database. To select a database amongst the multiples ones we use the SQL USE command. Syntax Follow this syntax to select a specific… Read More »
In SQL we have various operators to perform operations on data, and an operator can be represented by a special symbol or by a reserved character. Operators always used along with the SQL statements and they come very handy to perform reading and writing operations. The operators in SQL are divided into 3 major categories: Arithmetic operators Comparison… Read More »
When we use two or more than two combinations of values, operators and SQL functions, then it is considered as an expression. We write an expression as a statement or query which act as a formula to show some output. We often use various expressions to query a database. Expression Syntax SELECT column_name_1, column_name_2, column_name_N FROM table_name WHERE… Read More »
The first step of using SQL is creating a Database, and in Relational Database Management System to create a Database we use the CREATE SQL command. As in the previous SQL tutorials we have mentioned that we cannot have two databases with a similar name so before you name your database make sure that the similar name database… Read More »
Once we have created a database in SQL, we can also delete it by using the SQL DROP command. Syntax follow this syntax to delete a database: DROP DATABASE Database_name; Example let first create a temporary database. CREATE DATABASE temp_db; Output Query OK, 1 row affected (0.29 sec) Verify if the database is created: SHOW DATABASES; Output +——————–+… Read More »
