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Let us create a stored procedure and select return value from MySQL prepared statement −mysql> DELIMITER // mysql> CREATE PROCEDURE return_value() -> BEGIN -> SET @returnQuery= 'SELECT 98 INTO @value'; -> PREPARE stmt FROM @returnQuery; -> EXECUTE stmt; -> END -> // Query OK, 0 rows affected (0.20 sec) mysql> DELIMITER ;Call stored procedure using CALL command.mysql> call return_value(); Query OK, 1 row affected (0.07 sec)Display value using select statement −mysql> select @value;outputThis will produce the following output −+--------+ | @value | +--------+ | 98 | +--------+ 1 row in set (0.00 sec)
Yes, you can use ORDER BY DESC with GROUP BY. Let us first create a table −mysql> create table DemoTable -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> PostMessage varchar(100) -> ); Query OK, 0 rows affected (0.69 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(PostMessage) values('Hi'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable(PostMessage) values('Hello'); Query OK, 1 row affected (0.16 sec) mysql> insert into DemoTable(PostMessage) values('Hi'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable(PostMessage) values('Awesome'); Query OK, ... Read More
Use ISNULL() from MySQL. Let us first create a table −mysql> create table DemoTable -> ( -> Number1 int, -> Number2 int -> ); Query OK, 0 rows affected (0.59 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values(10, NULL); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable values(NULL, NULL); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable values(29, 98); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable values(NULL, 119); Query OK, 1 row affected (0.15 sec)Display all records ... Read More
The AUTO_INCREMENT=5 in a create table query tells that the first record will start from 5 i.e. not default 1. As we know if you do not set the value to AUTO_INCREMENT then MySQL starts from 1 by default.The syntax is as follows:CREATE TABLE yourTableName ( yourColumnName1 dataType NOT NULL AUTO_INCRMENT, . . . N, PRIMARY KEY(yourColumnName1 ) )AUTO_INCREMENT=5;To understand the above syntax, let us create a table.Case1 − The table starts auto increment from 1 because it is the default standard.The query to create a table is as follows:mysql> create table defaultAutoIncrementDemo -> ( -> Id int ... Read More
Let us first create a table −mysql> create table DemoTable -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> Name varchar(100), -> Subject varchar(100), -> Score int -> ); Query OK, 0 rows affected (0.94 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(Name, Subject, Score) values('Chris', 'MySQL', 80); Query OK, 1 row affected (0.32 sec) mysql> insert into DemoTable(Name, Subject, Score) values('Robert', 'MongoDB', 45); Query OK, 1 row affected (0.62 sec) mysql> insert into DemoTable(Name, Subject, Score) values('Adam', 'Java', 78); Query OK, 1 row affected ... Read More
Use IS NOT NULL to display only NOT NULL records. Let us first create a table −mysql> create table DemoTable -> ( -> FirstName varchar(100) -> ); Query OK, 0 rows affected (3.01 sec)Insert some records in the table using insert command −mysql> insert into DemoTable values('John'); Query OK, 1 row affected (0.44 sec) mysql> insert into DemoTable values(NULL); Query OK, 1 row affected (0.58 sec) mysql> insert into DemoTable values('Chris'); Query OK, 1 row affected (0.31 sec) mysql> insert into DemoTable values(NULL); Query OK, 1 row affected (0.20 sec) mysql> insert into ... Read More
If you want to login as a different user on MySQL, you need to use “mysql -u -p command”. The syntax is as follows to login as a different user.>mysql -u yourUsername -p After pressing enter key Enter password −To understand the above syntax, let us create a user in MySQL. The syntax is as follows −CREATE USER 'yourUserName'@'localhost' IDENTIFIED BY 'yourPassword';Now I am going to create a user with name ‘John’ and password is ‘john123456’. The query is as follows −mysql> CREATE USER 'John'@'localhost' IDENTIFIED BY 'john123456'; Query OK, 0 rows affected (0.15 sec)Now check the user has been ... Read More
For this, use ORDER BY DESC with LIMIT 1. Let us first create table −mysql> create table DemoTable -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> UserName varchar(100), -> UserMessage text -> ); Query OK, 0 rows affected (1.17 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(UserName, UserMessage) values('Adam', 'Hi'); Query OK, 1 row affected (0.92 sec) mysql> insert into DemoTable(UserName, UserMessage) values('Chris', 'Awesome'); Query OK, 1 row affected (0.52 sec) mysql> insert into DemoTable(UserName, UserMessage) values('Robert', 'Nice'); Query OK, 1 row affected (0.65 sec) ... Read More
For this, you can use SHOW VARIABLES command −mysql> SHOW VARIABLES LIKE 'auto_inc%';OutputThis will produce the following output −+--------------------------+-------+ | Variable_name | Value | +--------------------------+-------+ | auto_increment_increment | 1 | | auto_increment_offset | 1 | +--------------------------+-------+ 2 rows in set (0.95 sec)You can control over AUTO_INCREMENT outside.Let us first create a table −mysql> create table DemoTable -> ( -> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY -> ); Query OK, 0 rows affected (0.94 sec)Insert some records in the table using insert command −mysql> insert into DemoTable ... Read More
Yes, we can do this by first using CAST(). Let us first create a table −mysql> create table DemoTable -> ( -> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> StudentScore varchar(100) -> ); Query OK, 0 rows affected (0.66 sec)Insert some records in the table using insert command −mysql> insert into DemoTable(StudentScore) values('90'); Query OK, 1 row affected (0.21 sec) mysql> insert into DemoTable(StudentScore) values('100'); Query OK, 1 row affected (0.13 sec) mysql> insert into DemoTable(StudentScore) values('56'); Query OK, 1 row affected (0.10 sec) mysql> insert into DemoTable(StudentScore) values('98'); Query OK, 1 ... Read More