MySQL Group By
Data can be grouped by “group by” key-word. tbllibrary table structure and current status of the tbllibrary. Group by the writer and count the records for each writer. Explanation There are four groups by...
Data can be grouped by “group by” key-word. tbllibrary table structure and current status of the tbllibrary. Group by the writer and count the records for each writer. Explanation There are four groups by...
We have seen the SQL SELECT command along with the WHERE caluse to fetch data from a MySQL table, but when we try to give a condition, which compares the field or column value...
The MySQL LIMIT clause is used to narrow or limit, a result set to the specified number of rows. The LIMIT clause accepts one or two arguments, one is offset and another one is...
The comparison operators discussed so far have compared one value, exactly to one other value. Such precision may not always be desired or necessary. For this purpose MySQL provides the LIKE. The LIKE allows...
In order to select data that is within a range of values, the BETWEEN operator is used. The BETWEEN operator allows the selection of rows that contain values with a specified lower and upper...
The data return by a SELECT query can be sorted into a specified order using ORDER BY clause. Syntax: SELECT column-name FROM table-name ORDER BY column-name; When the ORDER BY keywords are followed by...
AND, OR, In, NOT In these all are called logical operators: AND(&&) : The AND operator allows creating an SQL statement based on two or more conditions being met. It can be used in...
A WHERE Clause is an SQL query to apply a filter on the rows retrieved. When a WHERE Clause is added to MySQL query, the MySQL engine compares each record in the table with...
A table could hold duplicate rows. In such a case, to view only unique rows the distinct clause can be used. The DISTINCT clause allows removing duplicates from the result set. The DISTINCT clause can...
A SELECT query can return the data from multiple columns by including the required column names as a comma-separated list in the query. The syntax to get multiple column data looks like this: If...
Data can be inserted in to an existing database table with an INSERT INTO query that first specified the table name. The SQL VALUES keyword then specifies the actual data to be inserted as comma-separated...
The format of an existing database table can be changed with an ALTER TABLE query . This query can make a single alteration or specify as number of alterations as comma-separated list. In the...
Modifiers can optionally be used to further control column content. NOT NULL UNIQUE AUTO_INCREMENT DEFAULT PRIMARY_KEY NOT NULL Insists that each record must include a data value in this column. This allows an empty...
This tutorial demonstrates how to SQL statement that creates MySQL database tables in which to store data. A simple database table look like this : Creating a database : CREATE DATABASE YOUR_DATABASE_NAME; In MySQL ...