Online Tutorials | C#, Python, MySQL, Excel
How to Use the COUNTBLANK Function in Excel In this tutorial, you’ll learn how to use the Excel COUNTBLANK function to count blank cells. When you are managing data in Excel, such as the number of people who attended an event or took a test, there may come a time when you want to know how … Read more
How to Use the MySQL SUBSTRING_INDEX() Function In this tutorial, you’ll learn how to use the MySQL SUBSTRING_INDEX() function. SUBSTRING_INDEX() returns a substring of a given string before a specified number of occurrences of delimiter. MySQL SUBSTRING_INDEX() Syntax The syntax of the SUBSTRING_INDEX() function is as follows: SUBSTRING_INDEX(string, delimiter, count) Arguments String: Required. The text from which you … Read more
How to Use The MySQL EXISTS Operator In this tutorial, you will learn how to use the MySQL EXISTS operator. MySQL EXIST operator is often used in subqueries to test whether any record in a subquery exists. If the subquery returns one or more records, the EXISTS operator returns true; otherwise, it returns false. Learn … Read more
How to Use the ROW_NUMBER Function in MySQL In this tutorial, you’ll learn how to use the MySQL ROW_NUMBER function. ROW_NUMBER returns the number of the current record within its partition of a result set. MySQL ROW_NUMBER() Syntax The syntax of the ROW_NUMBER() function is as follows: ROW_NUMBER() OVER( PARTITION BY expression [, expression], … ORDER BY expression [ASC | DESC], [, expression], … Read more
How to concatenate strings using the MySQL CONCAT() function and examples This tutorial explains how to concatenate strings using the MySQL CONCAT() function. You will learn how to use the MySQL CONCAT() function, which is a function that adds two or more expressions together. Learn more: MySQL GROUP_CONCAT() function MySQL CONCAT() Syntax CONCAT(expression1, expression2,…, expressionN) … Read more
How to Use the MySQL IN Operator In this tutorial, you will learn how to use the MySQL IN operator.MySQL IN operator is used to check whether a value is within a set of values. Other tutorials: How to use the LIKE operator in MySQL MySQL IN Syntax The syntax of the IN operator is … Read more
How to Use the SUMIFS Function in Excel In this tutorial, you’ll learn how to use the Excel SUMIFS function to sum cells that match multiple criteria. When aggregating in Excel, you may want to calculate the sum of numerical values that satisfy multiple conditions.The SUMIFS function allows you to find the sum of numbers that … Read more
How to Show Tables in MySQL In this tutorial, you’ll learn how to show a list of tables in MySQL using the SHOW TABLES statement. MySQL SHOW TABLES Syntax The syntax of the SHOW TABLES statement is as follows: SHOW TABLES [{FROM | IN} database_name] [WHERE where_expression | LIKE ‘pattern’] Remarks Database_name: The name of the database … Read more
How to Use the COUNTIFS Function in Excel In this tutorial, you’ll learn how to use the Excel COUNTIFS function. COUNTIFS() is a function to count the number of cells in a range that meet multiple criteria. You can use COUNTIFS() to count cells that contain dates, numbers, or references containing numbers. COUNTIFS() Syntax The syntax of the COUNTIFS() function … Read more
How to Use the GROUP BY Clause in MySQL In this tutorial, you’ll learn how to use the MySQL GROUP BY clause in the SELECT query to group a set of records into summary records. GROUP BY is used to group a set of records by one or more columns, and we often use it with aggregate functions such as COUNT(), SUM(), AGV(), MAX(), … Read more
How to Use the ORDER BY Clause in MySQL with Examples In this tutorial, you will learn to retrieve rows of a table sorted in ascending or descending order from a MySQL database. To get the rows sorted in ascending or descending order, we use MySQL ORDER BY clause along with a SELECT statement. The syntax … Read more
How to Use the MySQL CREATE DATABASE Statement In this tutorial, you’ll learn how to create a new database in MySQL using the CREATE DATABASE statement. CREATE DATABASE Syntax To create a database, you use the CREATE DATABASE statement as follows: CREATE DATABASE [IF NOT EXISTS] database_name [CHARACTER SET charset_name] [COLLATE collation_name] Remarks Database_name must be unique within the MySQL … Read more
How to Create Tables in MySQL Using the CREATE TABLE Statement In this tutorial, you will learn how to create a table in MySQL using the MySQL CREATE TABLE statement. Learn more: Delete a table in MySQL ALTER TABLE statement in MySQL ADD COLUMN statement in MySQL CREATE TABLE Syntax The syntax of the MySQL CREATE TABLE … Read more
How to Use LEFT JOIN in MySQL In this tutorial, you’ll learn how to use the MySQL LEFT JOIN. LEFT JOIN is used to select all records from the left table and the matched records from the right table. LEFT JOIN Syntax SELECT column_name(s)FROM table1LEFT JOIN table2 ON table1.column_name = table2.column_nam Examples Suppose you have two tables, … Read more
How to Use the Excel AVERAGEIF Function In this tutorial, you’ll learn how to use the Excel AVERAGEIF function. AVERAGEIF is a function to calculate the average of a group of numbers in a range of cells that meet single criteria. AVERAGEIF Syntax The syntax of the AVERAGEIF() function is as follows: =AVERAGEIF (range, criteria, [average_range]) Arguments range: A range … Read more
How to Use the ALTER TABLE Statement In this tutorial, you’ll learn how to use the MySQL ALTER TABLE statement to add, drop, and modify columns in an existing table. You also can use the ALTER TABLE statement to add and drop a primary key, a foreign key, and other constraints on the table. Adding a single column using … Read more
How to Use INDEX and MATCH with Examples In this tutorial, you’ll learn how to use the combination of INDEX() and MATCH() to lookup a value and retrieve some other related information. First, learn INDEX() and MATCH(), and second, learn to use the combination of INDEX() and MATCH(). INDEX INDEX() returns a value or a reference to specified cells from within … Read more
How to Use the MySQL CASE Statement In this tutorial, you will learn how to use the MySQL CASE statement, a flow control statement in MySQL that allows you to execute a block of SQL code when one condition is TRUE and another block of SQL code when that condition evaluates to FALSE. Learn more: … Read more
How to Use the MySQL DATE_FORMAT() Function In this tutorial, you’ll learn how to use the MySQL DATE_FORMAT() function. DATE_FORMAT() formats a date as specified. MySQL DATE_FORMAT() Syntax The syntax of the DATE_FORMAT() function is as follows: DATE_FORMAT(date, format) Arguments date: Required. The date that you want to format. format: Required. The format to use. … Read more
How to Use the foreach Statement in C# This tutorial describes how to use the foreach statement with examples in C#. The foreach statement executes a block of code for each element of a given collection, such as a list, dictionary, or array. Related C# tutorials: A for loop statement in C# A while loop … Read more