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Found 6705 Articles for Database

2K+ Views
To check records which are NULL, use IS NULL. However, to exclude any of the records, use the NOT IN clause. Use both of them in the same query.Let us first create a table −mysql> create table DemoTable793 ( StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentName varchar(100) ); Query OK, 0 rows affected (0.81 sec)Insert some records in the table using insert command −mysql> insert into DemoTable793(StudentName) values('Adam'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable793(StudentName) values('Bob'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable793(StudentName) values(null); Query ... Read More

148 Views
To reshuffle the values in a table, use MySQL RAND().Let us first create a table −mysql> create table DemoTable792 ( Name varchar(100), Subject varchar(100) ); Query OK, 0 rows affected (0.66 sec)Insert some records in the table using insert command −mysql> insert into DemoTable792 values('Chris', 'MySQL'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable792 values('David', 'MySQL'); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable792 values('Robert', 'MongoDB'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable792 values('Carol', 'MongoDB'); Query OK, 1 row affected (0.18 sec)Display all records ... Read More

2K+ Views
Use NOT IN() to exclude some of the values from the table.Let us first create a table −mysql> create table DemoTable791 ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, FirstName varchar(100) ); Query OK, 0 rows affected (0.61 sec)Insert some records in the table using insert command −mysql> insert into DemoTable791(FirstName) values('Chris'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable791(FirstName) values('Robert'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable791(FirstName) values('David'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable791(FirstName) values('Mike'); Query OK, 1 row affected (0.11 ... Read More

183 Views
Let us first create a table −mysql> create table DemoTable790 ( Score1 int, Score2 int ); Query OK, 0 rows affected (0.45 sec)Insert some records in the table using insert command −mysql> insert into DemoTable790 values(98, 76); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable790 values(78, 89); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable790 values(85, 68); Query OK, 1 row affected (0.14 sec)Display all records from the table using select statement −mysql> select *from DemoTable790;This will produce the following output -+--------+--------+ | Score1 | Score2 | +--------+--------+ ... Read More

833 Views
To check for the 1st letter of the first and last name, you need to use the LEFT().Let us first create a table −mysql> create table DemoTable789 ( FirstName varchar(100), LastName varchar(100) ); Query OK, 0 rows affected (0.78 sec)Insert some records in the table using insert command −mysql> insert into DemoTable789 values('Adam', 'Smith'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable789 values('Tom', 'Taylor'); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable789 values('Bob', 'Brown'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable789 values('David', 'Miller'); Query ... Read More

501 Views
Use ORDER BY to sort data for duplicate record.Let us first create a table −mysql> create table DemoTable788 ( FirstName varchar(100), Score int ); Query OK, 0 rows affected (1.89 sec)Insert some records in the table using insert command −mysql> insert into DemoTable788 values('Chris', 78); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable788 values('Robert', 67); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable788 values('Chris', 98); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable788 values('Chris', 56); Query OK, 1 row affected (0.15 sec) mysql> insert into ... Read More

2K+ Views
Let us first create a table −mysql> create table DemoTable787 ( Score1 int, Score2 int, Name varchar(100) ); Query OK, 0 rows affected (0.84 sec)Insert some records in the table using insert command −mysql> insert into DemoTable787 values(34, 56, 'Chris'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable787 values(73, 86, 'Robert'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable787 values(90, 99, 'David'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable787 values(80, 89, 'Adam'); Query OK, 1 row affected (0.21 sec)Display all records ... Read More

673 Views
To display column values as CSV, use GROUP_CONCAT().Let us first create a table −mysql> create table DemoTable786 ( StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentName varchar(100) ) AUTO_INCREMENT=101; Query OK, 0 rows affected (0.70 sec)Insert some records in the table using insert command −mysql> insert into DemoTable786(StudentName) values('Chris'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable786(StudentName) values('Robert'); Query OK, 1 row affected (0.24 sec) mysql> insert into DemoTable786(StudentName) values('Mike'); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable786(StudentName) values('Sam'); Query OK, 1 row affected (0.12 sec)Display all records from the table ... Read More

204 Views
For specific day of week, use DAYOFWEEK().Let us first create a table −mysql> create table DemoTable785 ( CustomerId int NOT NULL AUTO_INCREMENT PRIMARY KEY, CustomerName varchar(100), ShoppingDate date ); Query OK, 0 rows affected (0.61 sec)Insert some records in the table using insert command −mysql> insert into DemoTable785(CustomerName, ShoppingDate) values('Chris', '2019-07-03'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable785(CustomerName, ShoppingDate) values('Robert', '2019-07-01'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable785(CustomerName, ShoppingDate) values('David', '2019-07-06'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable785(CustomerName, ShoppingDate) ... Read More

218 Views
To ignore quotes while ordering column values, use ORDER BY TRIM().Let us first create a table −mysql> create table DemoTable784 ( Message varchar(100) ); Query OK, 0 rows affected (0.50 sec)Insert some records in the table using insert command −mysql> insert into DemoTable784 values('Good'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable784 values('\"This is not a Message\"'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable784 values('Bye'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable784 values('Hello'); Query OK, 1 row affected (0.15 sec)Display all records from the table using ... Read More