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To select last two rows, use ORDER BY DESC LIMIT 2.Let us first create a table −mysql> create table DemoTable763 ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, FirstName varchar(100) ); Query OK, 0 rows affected (0.57 sec)Insert some records in the table using insert command −mysql> insert into DemoTable763(FirstName) values('John'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable763(FirstName) values('Sam'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable763(FirstName) values('Carol'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable763(FirstName) values('David'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable763(FirstName) ... Read More
For this, you can use LIKE operator with OR condition.Let us first create a table −mysql> create table DemoTable762 (Title text); Query OK, 0 rows affected (0.54 sec)Insert some records in the table using insert command −mysql> insert into DemoTable762 values('Introduction to Java'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable762 values('MySQL is a RDBMS'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable762 values('Data Structure and Algorithm in Java'); Query OK, 1 row affected (0.21 sec) mysql> insert into DemoTable762 values('Data Structure and Algorithm in C and C++'); Query OK, 1 row affected (0.18 ... Read More
The strings (column values) begun with a character and rest of the string has numbers. We want the sum of these numbers −J230 A130s C13For this, use SUBSTRING() function along with SUM().Let us first create a table −mysql> create table DemoTable761 (Price varchar(100)); Query OK, 0 rows affected (0.62 sec)Insert some records in the table using insert command −mysql> insert into DemoTable761 values('J230'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable761 values('A130'); Query OK, 1 row affected (0.70 sec) mysql> insert into DemoTable761 values('C13'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable761 values('D456'); Query ... Read More
Let us first create a table −mysql> create table DemoTable760 ( ClientId int, ClientId2 int ); Query OK, 0 rows affected (0.79 sec)Insert some records in the table using insert command −mysql> insert into DemoTable760 values(100, 200); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable760 values(100, 200); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable760 values(300, 400); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable760 values(300, 400); Query OK, 1 row affected (0.26 sec) mysql> insert into DemoTable760 values(100, 200); Query OK, 1 row affected (0.23 sec) mysql> insert ... Read More
To set NULL values, set the type as NULL as in the below syntax −yourColumnName dataType NULL;Let us first create a table −mysql> create table DemoTable759 ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, FirstName varchar(100) NULL ); Query OK, 0 rows affected (0.72 sec)Insert some records in the table using insert command −mysql> insert into DemoTable759(FirstName) values('John'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable759(FirstName) values(NULL); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable759(FirstName) values('Carol'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable759(FirstName) values(NULL); Query OK, 1 row ... Read More
To set the default value, use the DEFAULT keyword.Let us first create a table −mysql> create table DemoTable758 ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, FirstName varchar(100) ); Query OK, 0 rows affected (0.66 sec)Following is the query to set default value for a column −mysql> alter table DemoTable758 add column Colors ENUM('RED', 'GREEN', 'BLUE', 'ORANGE', 'YELLOW') DEFAULT 'YELLOW'; Query OK, 0 rows affected (0.44 sec) Records: 0 Duplicates: 0 Warnings: 0Let us check the description of table once again −mysql> desc DemoTable758;This will produce the following output -+-----------+----------------------------------------------+------+-----+---------+----------------+ | Field | Type ... Read More
Let’s say you have a VARCHAR column in a table with values are strings and the numbers are on the right side. For example −John1023 Carol9871 David9098Now, consider you want to order by on the basis of these right-side numbers in the entire column. For this, use ORDER BY RIGHT.Let us first create a table −mysql> create table DemoTable757 ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, ClientId varchar(100) ); Query OK, 0 rows affected (0.53 sec)Insert some records in the table using insert command −mysql> insert into DemoTable757(ClientId) values('John1023'); Query OK, 1 row ... Read More
Let us first create a table −mysql> create table DemoTable756 ( Value1 int, Value2 int, Value3 int ); Query OK, 0 rows affected (0.62 sec)Insert some records in the table using insert command −mysql> insert into DemoTable756 values(10, 20, 14); Query OK, 1 row affected (0.22 sec) mysql> insert into DemoTable756 values(20, 34, 17); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable756 values(200, 134, 789); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable756 values(139, 98, 99); Query OK, 1 row affected (0.17 sec)Display all records from the table using select statement ... Read More
For this, use alias on HAVING clause.Let us first create a table −mysql> create table DemoTable755 ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, Score1 int, Score2 int ); Query OK, 0 rows affected (0.62 sec)Insert some records in the table using insert command −mysql> insert into DemoTable755(Score1, Score2) values(30, 23); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable755(Score1, Score2) values(50, 60); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable755(Score1, Score2) values(89, 90); Query OK, 1 row affected (0.29 sec) mysql> insert into DemoTable755(Score1, Score2) values(99, 99); Query OK, 1 row ... Read More
To return only the distinct values, use GROUP BY clause.Let us first create a table −mysql> create table DemoTable754 (ProductPrice int); Query OK, 0 rows affected (0.48 sec)Insert some records in the table using insert command −mysql> insert into DemoTable754 values(200); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable754 values(500); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable754 values(200); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable754 values(500); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable754 values(800); Query OK, 1 row affected (0.24 sec) mysql> insert into DemoTable754 ... Read More