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Let us first create a table −mysql> create table DemoTable ( Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, FirstName varchar(100) ); Query OK, 0 rows affected (0.46 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(FirstName) values('Chris'); Query OK, 1 row affected (0.18 sec) mysql> insert into DemoTable(FirstName) values('Robert'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable(FirstName) values('Robert'); Query OK, 1 row affected (0.07 sec) mysql> insert into DemoTable(FirstName) values('John'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable(FirstName) values('John'); Query OK, 1 row affected (0.11 sec) mysql> insert ... Read More
Let us first create a table −mysql> create table DemoTable ( FirstName varchar(100), LastName varchar(100) ); Query OK, 0 rows affected (0.76 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris', 'Brown'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values('Adam', 'Smith'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('Carol', 'Taylor'); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values('David', 'Miller'); Query OK, 1 row affected (0.12 sec)Display all records from the table using select statement −mysql> select *from DemoTable;This will produce the ... Read More
To update a field if it is null, use IS NULL property along with the UPDATE command. Let us first create a table −mysql> create table DemoTable ( StudentScore int ); Query OK, 0 rows affected (0.47 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(89); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values(NULL); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(45); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable values(NULL); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values(56); ... Read More
To insert values from the first table to another table using two SELECT statements, use SUBQUERY. This will allow you to use only a single MySQL query to get the result in the second table. Let us first create a table −mysql> create table DemoTable1 ( Name varchar(100), Score int ); Query OK, 0 rows affected (1.30 sec)Insert some records in the table using insert command −mysql> insert into DemoTable1 values('Chris', 45); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable1 values('Bob', 78); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable1 values('David', 98); ... Read More
For this, let us first create a table −mysql> create table DemoTable ( Message text ); Query OK, 0 rows affected (1.15 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Good'); Query OK, 1 row affected (0.43 sec) mysql> insert into DemoTable values('Bye'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable values('Awesome'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values('Bye'); Query OK, 1 row affected (0.08 sec) mysql> insert into DemoTable values('Good'); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable values('Amazing'); Query OK, 1 ... Read More
To set the default value in MySQL, you need to use the DEFAULT keyword. Let us first create a table −mysql> create table DemoTable ( ClientCountryName varchar(100) DEFAULT 'NONE' ); Query OK, 0 rows affected (0.65 sec)We have set DEFAULT above for values not entered while insertion. Now, let us insert some records in the table using the insert command. We haven’t inserted values here for some of the rows. The DEFAULT gets set there −mysql> insert into DemoTable values('US'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values(); Query OK, 1 row affected (0.09 sec) ... Read More
To fetch number of characters from the left of the string, use the LEFT method in MySQL. Let us first create a table −mysql> create table DemoTable ( Name varchar(100) ); Query OK, 0 rows affected (6.58 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Sam Brown'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable values('David Miller'); Query OK, 1 row affected (0.20 sec) mysql> insert into DemoTable values('Adam Smith'); Query OK, 1 row affected (7.01 sec) mysql> insert into DemoTable values('Carol Taylor'); Query OK, 1 row affected (0.68 sec)Display all ... Read More
Yes, we can use the SELECT NULL statement in a MySQL query. Let us first create a table −mysql> create table DemoTable ( Name varchar(100) ); Query OK, 0 rows affected (0.49 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris'); Query OK, 1 row affected (0.47 sec) mysql> insert into DemoTable values('Mike'); Query OK, 1 row affected (0.23 sec) mysql> insert into DemoTable values('Sam'); Query OK, 1 row affected (0.19 sec) mysql> insert into DemoTable values('Bob'); Query OK, 1 row affected (0.27 sec) mysql> insert into DemoTable values('David'); Query OK, 1 row affected ... Read More
For this, use ORDER BY DESC with the LIMIT clause. The ORDER BY DESC order in descending order where LIMIT sets the number of records you want. Here, we will set LIMIT 1 since we want only a single record. Let us first create a table −mysql> create table DemoTable ( StudentName varchar(100), StudentMarks int ); Query OK, 0 rows affected (0.54 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('Chris', 45); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable values('Bob', 78); Query OK, 1 row affected (0.16 sec) mysql> ... Read More
Let us first create a table −mysql> create table DemoTable ( Score int ); Query OK, 0 rows affected (0.65 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(45); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values(29); Query OK, 1 row affected (0.11 sec) mysql> insert into DemoTable values(56); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable values(24); Query OK, 1 row affected (0.09 sec) mysql> insert into DemoTable values(32); Query OK, 1 row affected (0.09 sec)Display all records from the table using select statement −mysql> select ... Read More