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Use RAND() for random, whereas LIMIT 3 for the number of values i.e. 3 here −select yourColumnName from yourTableName order by rand() limit 3;Let us first create a table −mysql> create table DemoTable646 ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, FirstName varchar(100) ); Query OK, 0 rows affected (0.76 sec)Insert some records in the table using insert command −mysql> insert into DemoTable646(FirstName) values('John'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable646(FirstName) values('Bob'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable646(FirstName) values('Chris'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable646(FirstName) ... Read More
For this, use UNION. Let us first create a table −mysql> create table DemoTable645 (Id int, FirstName varchar(100)); Query OK, 0 rows affected (0.67 sec)Insert some records in the table using insert command −mysql> insert into DemoTable645 values(100, 'Chris'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable645 values(101, 'Robert'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable645 values(101, 'Bob'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable645 values(102, 'Carol'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable645 values(100, 'John'); Query OK, 1 row affected (0.12 sec) mysql> insert ... Read More
Graphs come with various properties which are used for characterization of graphs depending on their structures. These properties are defined in specific terms pertaining to the domain of graph theory. In this chapter, we will discuss a few basic properties that are common in all graphs.Radius of a Connected GraphThe minimum eccentricity from all the vertices is considered as the radius of the Graph G. The minimum among all the maximum distances between a vertex to all other vertices is considered as the radius of the Graph G.Notation − r(G)From all the eccentricities of the vertices in a graph, the ... Read More
A graph is a diagram of points and lines connected to the points. It has at least one line joining a set of two vertices with no vertex connecting itself. The concept of graphs in graph theory stands up on some basic terms such as point, line, vertex, edge, degree of vertices, properties of graphs, etc. Here, in this chapter, we will cover these fundamentals of graph theory.PointA point is a particular position in a one-dimensional, two-dimensional, or three-dimensional space. For better understanding, a point can be denoted by an alphabet. It can be represented with a dot.ExampleHere, the dot ... Read More
For this, use CONCAT(). Let us first create a table −mysql> create table DemoTable644 (Title text); Query OK, 0 rows affected (0.81 sec)Insert some records in the table using insert command −mysql> insert into DemoTable644 values('Introduction'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable644 values('Welcome in course'); Query OK, 1 row affected (0.10 sec)Display all records from the table using select statement −mysql> select *from DemoTable644;This will produce the following output −+-------------------+ | Title | +-------------------+ | Introduction | | Welcome in course | +-------------------+ 2 rows ... Read More
Euler Graph - A connected graph G is called an Euler graph, if there is a closed trail which includes every edge of the graph G.Euler Path - An Euler path is a path that uses every edge of a graph exactly once. An Euler path starts and ends at different vertices.Euler Circuit - An Euler circuit is a circuit that uses every edge of a graph exactly once. An Euler circuit always starts and ends at the same vertex. A connected graph G is an Euler graph if and only if all vertices of G are of even degree, ... Read More
Let us first create a table −mysql> create table DemoTable643 (ClientId int); Query OK, 0 rows affected (0.86 sec)Insert some records in the table using insert command −mysql> insert into DemoTable643 values(1000); Query OK, 1 row affected (0.19 sec)Display all records from the table using select statement −mysql> select *from DemoTable643;This will produce the following output −+----------+ | ClientId | +----------+ | 1000 | +----------+ 1 row in set (0.00 sec)Here is the query to MySQL stored procedure with IF THEN END IF −mysql> DELIMITER // mysql> CREATE PROCEDURE IF_DEMO(argument int) BEGIN DECLARE firstArgument int; DECLARE ... Read More
Cardinality of a set S, denoted by |S|, is the number of elements of the set. The number is also referred as the cardinal number. If a set has an infinite number of elements, its cardinality is ∞.Example − |{1, 4, 3, 5}| = 4, |{1, 2, 3, 4, 5, ....}| = ∞If there are two sets X and Y, |X| = |Y| denotes two sets X and Y having same cardinality. It occurs when the number of elements in X is exactly equal to the number of elements in Y. In this case, there exists a bijective function ‘f’ ... Read More
Let us first create a table −mysql> create table DemoTable642( EmployeeId int NOT NULL AUTO_INCREMENT PRIMARY KEY, EmployeeName archar(100), EmployeeCompanyNamevarchar(100) ); Query OK, 0 rows affected (0.81 sec)Insert some records in the table using insert command −mysql> insert into DemoTable642(EmployeeName, EmployeeCompanyName) values('John', 'Google'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable642(EmployeeName, EmployeeCompanyName) values('Carol', 'Microsoft'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable642(EmployeeName, EmployeeCompanyName) values('John', 'Amazon'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable642(EmployeeName, EmployeeCompanyName) values('Carol', 'Google'); Query OK, 1 row affected (0.37 sec) mysql> insert into DemoTable642(EmployeeName, EmployeeCompanyName) values('John', 'Flipkart'); ... Read More
Let us first create a table −mysql> create table DemoTable1 (Id int, Name varchar(100)); Query OK, 0 rows affected (0.89 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1 values(100, 'John'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable1 values(110, 'Chris'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable1 values(120, 'Robert'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable1 values(130, 'David'); Query OK, 1 row affected (0.14 sec)Display all records from the table using select statement −mysql> select *from DemoTable1;This will produce the following output −+------+--------+ | ... Read More