MySQL where column = 'x, y, z'?

Samual Sam
Updated on 30-Jul-2019 22:30:25

469 Views

You can use IN operator for this.The syntax is as follows −SELECT *FROM yourTableName WHERE yourColumnName IN(‘yourValue1’, ‘yourValue2’, ‘yourValue3’, ...........N);To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table InOperatorDemo    -> (    -> ClientId int    -> ); Query OK, 0 rows affected (0.52 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert into InOperatorDemo values(101); Query OK, 1 row affected (0.19 sec) mysql> insert into InOperatorDemo values(110); Query OK, 1 row affected (0.11 sec) mysql> insert into InOperatorDemo ... Read More

MySQL query to skip the duplicate and select only one from the duplicated values

karthikeya Boyini
Updated on 30-Jul-2019 22:30:25

1K+ Views

The syntax is as follows to skip the duplicate value and select only one from the duplicated values −select min(yourColumnName1), yourColumnName2 from yourTableName group by yourColumnName2;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table doNotSelectDuplicateValuesDemo    -> (    -> User_Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> User_Name varchar(20)    -> ); Query OK, 0 rows affected (0.78 sec)Now you can insert some records in the table using insert command. The query is as follows −mysql> insert into doNotSelectDuplicateValuesDemo(User_Name) values('John'); Query OK, 1 row affected ... Read More

Add a temporary column in MySQL where the values depend on another column?

Samual Sam
Updated on 30-Jul-2019 22:30:25

2K+ Views

You can use CASE statement for this and set conditions to get result in the temporary column.Let us first create a table −mysql> create table DemoTable    (    EmployeeId int NOT NULL AUTO_INCREMENT PRIMARY KEY,    EmployeeName varchar(20),    EmployeeSalary int,    EmployeeExperience int    ); Query OK, 0 rows affected (0.64 sec)Following is the query to insert some records in the table using insert command −mysql> insert into DemoTable(EmployeeName, EmployeeSalary, EmployeeExperience) values('Larry', 4500, 5); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable(EmployeeName, EmployeeSalary, EmployeeExperience) values('Mike', 130000, 8); Query OK, 1 row affected (0.21 sec) mysql> ... Read More

Exact count of all rows in MySQL database?

Samual Sam
Updated on 30-Jul-2019 22:30:25

482 Views

To exactly count all rows, you need to use the aggregate function COUNT(*). The syntax is as follows −select count(*) as anyAliasName from yourTableName;To understand the above syntax, let us create a table. The query to create a table is as follows −mysql> create table CountAllRowsDemo    -> (    -> Id int,    -> Name varchar(10),    -> Age int    -> ); Query OK, 0 rows affected (1.49 sec)Now you can insert some records in the table using insert command. The query is as follows −mysql> insert into CountAllRowsDemo values(1, 'John', 23); Query OK, 1 row affected (0.15 ... Read More

Add a value to Septet class in JavaTuples

karthikeya Boyini
Updated on 30-Jul-2019 22:30:25

150 Views

The addAtX() method is used to add value to the Septet Tuple. The index can be set here with the X i.e. the place where the value gets added.Let us first see what we need to work with JavaTuples. To work with Septet class in JavaTuples, you need to import the following package −import org.javatuples.Septet;Note − Steps to download and run JavaTuples program If you are using Eclipse IDE to run Septet Class in JavaTuples, then Right Click Project → Properties → Java Build Path → Add External Jars and upload the downloaded JavaTuples jar file.The following is an example ... Read More

Rename Root @ localhost username in MySQL?

Ankith Reddy
Updated on 30-Jul-2019 22:30:25

767 Views

The syntax is as follows to rename Root @localhostUPDATE MySQL.user SET user = ‘yourNewRootName’ WHERE user = 'root';To understand the above concept, let us check all the user names and host. The query is as followsmysql> select user, host from MySQL.user;The following is the output+------------------+-----------+ | user             | host      | +------------------+-----------+ | Bob              | %         | | Manish           | %         | | User2            | %       ... Read More

Using MySQL SELECT for simple BOOLEAN evaluation?

Samual Sam
Updated on 30-Jul-2019 22:30:25

364 Views

You can use CASE statement for this. Let us see an example −mysql> create table BooleanEvaluationDemo    -> (    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,    -> FirstValue int,    -> SecondValue int    -> ); Query OK, 0 rows affected (0.71 sec)Insert some records in the table using insert command. The query is as follows −mysql> insert into BooleanEvaluationDemo(FirstValue, SecondValue) values(10, 5); Query OK, 1 row affected (0.20 sec) mysql> insert into BooleanEvaluationDemo(FirstValue, SecondValue) values(15, 20); Query OK, 1 row affected (0.16 sec) mysql> insert into BooleanEvaluationDemo(FirstValue, SecondValue) values(50, 40); Query OK, 1 row affected (0.14 ... Read More

Display IDs in a particular order with MySQL IN()?

karthikeya Boyini
Updated on 30-Jul-2019 22:30:25

337 Views

To display IDs in a particular order i.e. the order of your choice use FIELD() method.Let us first create a table −mysql> create table DemoTable    (    UserId int    ); Query OK, 0 rows affected (0.64 sec)Following is the query to insert some records in the table using insert command −mysql> insert into DemoTable values(100); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values(10); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values(40); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(80); Query OK, 1 row affected (0.13 sec) ... Read More

C++ Program to Find the Maximum Cut in a Graph

Nishtha Thakur
Updated on 30-Jul-2019 22:30:25

663 Views

In this program to find the maximum Cut in a graph, we need to find the Edge Connectivity of a Graph. An Edge Connectivity of a Graph of a graph means it is a bridge, removing it graph will be disconnected. Number of connected components increases with the removing of bridge in a disconnected undirected graph.Functions and pseudocodeBegin    Function connections() is a recursive function to find out the connections:    A) Mark the current node un visited.    B) Initialize time and low value    C) Go through all vertices adjacent to this    D) Check if the subtree ... Read More

Create Quartet Tuple from another collection in Java

Samual Sam
Updated on 30-Jul-2019 22:30:25

155 Views

Use the fromCollection() method to create Quartet Tuple from another collection i.e. we will see an example of List here.Let us first see what we need to work with JavaTuples. To work with Quartet class in JavaTuples, you need to import the following package −import org.javatuples.Quartet;Note − Steps to download and run JavaTuples program If you are using Eclipse IDE to run Quartet Class in JavaTuples, then Right Click Project → Properties → Java Build Path → Add External Jars and upload the downloaded JavaTuples jar file.The following is an example −Exampleimport java.util.*; import org.javatuples.Quartet; public class Demo {   ... Read More

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