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Let’s say, here I am using the WEB database. We need to find the number of tables in the database WEB. For this, use the INFORMATION_SCHEMA.TABLES in MySQL.Following is the query to display the number of tables −mysql> select count(table_name) as TotalNumberOfTablesInWebDatabase -> from information_schema.tables -> where table_schema='web';This will produce the following output −+----------------------------------+ | TotalNumberOfTablesInWebDatabase | +----------------------------------+ | 1562 | +----------------------------------+ 1 row in set (0.27 sec)To just check whether the count of records displayed above are the same or not, use the ... Read More
To sum, use the aggregate function SUM(). With that, group using MySQL GROUP BY. Let us first create a table −mysql> create table DemoTable -> ( -> ProductName varchar(20), -> ProductQuantity int, -> ProductPrice int -> ); Query OK, 0 rows affected (0.63 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Product-1', 2, 50); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('Product-2', 3, 80); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values('Product-2', 4, 100); Query OK, 1 row affected (0.11 sec) mysql> ... Read More
Yes, we can set a single value with IN() in MySQL. Let us first create a table−mysql> create table DemoTable -> ( -> FirstName varchar(20) -> ); Query OK, 0 rows affected (0.65 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris'); Query OK, 1 row affected (0.42 sec) mysql> insert into DemoTable values('David'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values('Mike'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values('Bob'); Query OK, 1 row affected (0.08 sec)Display all records from the table using select ... Read More
Yes, we can change the order of columns. This can be done using ALTER command and AFTER to set the new order of an individual column. Let us first create a table −mysql> create table DemoTable -> ( -> `Student_Key_Age` int, -> `Student_Key_Name` varchar(20), -> `Student_Key_CountryName` varchar(20) -> ); Query OK, 0 rows affected (0.64 sec)Following is the query to alter order of columns −mysql> alter table DemoTable modify column `Student_Key_Age` int after `Student_Key_Name`; Query OK, 0 rows affected (1.15 sec) Records: 0 Duplicates: 0 Warnings: 0Let us check the table description once again −mysql> ... Read More
Let us first create a table −mysql> create table DemoTable -> ( -> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> StudentName varchar(20), -> StudentMarks int, -> Status varchar(20) -> ); Query OK, 0 rows affected (0.97 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(StudentName, StudentMarks) values('Chris', 79); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable(StudentName, StudentMarks) values('David', 59); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable(StudentName, StudentMarks) values('Bob', 60); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable(StudentName, StudentMarks) values('Mike', ... Read More
To perform custom sorting in MySQL, use ORDER BY FIELD(). Let us first create a table −mysql> create table DemoTable -> ( -> Id int -> ); Query OK, 0 rows affected (0.82 sec)Insert some records in the table using insert command:mysql> insert into DemoTable values(101); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable values(103); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values(102); Query OK, 1 row affected (0.08 sec) mysql> insert into DemoTable values(105); Query OK, 1 row affected (0.14 sec)Display all records from the table using select statement ... Read More
Let us first create a table −mysql> create table DemoTable -> ( -> Id int, -> Name varchar(20) -> ); Query OK, 0 rows affected (0.93 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(101, 'Chris'); Query OK, 1 row affected (0.25 sec) mysql> insert into DemoTable values(102, 'David'); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable values(103, 'Robert'); Query OK, 1 row affected (0.16 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output−+------+--------+ | Id | Name ... Read More
Let us first create a table −mysql> create table DemoTable -> ( -> EmailAddress varchar(20), -> Score int -> ); Query OK, 0 rows affected (1.05 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris@gmail.com', 67); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values('Robert@gmail.com', 57); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable values('David@gmail.com', 98); Query OK, 1 row affected (0.14 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the following output −+------------------+-------+ | EmailAddress ... Read More
To remove trailing space, use RTRIM() in MySQL. Let us first create a table −mysql> create table DemoTable -> ( -> FirstName varchar(50) -> ); Query OK, 0 rows affected (1.38 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John '); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('Chris '); Query OK, 1 row affected (0.51 sec) mysql> insert into DemoTable values(' David '); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Mike'); Query OK, 1 row affected (0.17 sec)Display all records from the table ... Read More
Let us first create a table −mysql> create table DemoTable -> ( -> Id int, -> Name varchar(20) -> ); Query OK, 0 rows affected (0.60 sec)Insert some records in the table using insert command:Insert some records in the table using insert command: mysql> insert into DemoTable values(100, 'Bob'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(101, 'Chris'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values(102, 'David'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(103, 'Sam'); Query OK, 1 row affected (0.08 sec) mysql> ... Read More