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The correct datetime format for MySQL database is as follows −‘YYYY-MM-DD HH:M:SS’Let us first create a table −mysql> create table DemoTable797 ( ArrivalDatetime datetime ); Query OK, 0 rows affected (0.68 sec)Insert some records in the table using insert command −mysql> insert into DemoTable797 values(NOW()); Query OK, 1 row affected (0.15 sec) mysql> insert into DemoTable797 values('2016-12-21 12:50:34'); Query OK, 1 row affected (0.17 sec) mysql> insert into DemoTable797 values('2017-03-01 17:40:21'); Query OK, 1 row affected (0.24 sec)Display all records from the table using select statement −mysql> select *from DemoTable797;This will produce the following output. We have ... Read More
Whenever you want to restrict the type parameter to subtypes of a particular class you can use the bounded type parameter. If you just specify a type (class) as bounded parameter, only sub types of that particular class are accepted by the current generic class.You can declare a bound parameter just by extending the required class with the type-parameter, within the angular braces as −class Sample Example Live DemoIn the following Java example the generic class Sample restricts the type parameter to the sub classes of the Number classes using the bounded parameter.class Sample { T data; Sample(T data){ ... Read More
Use the DAYNAME() to display the day name from records with Date of Birth.Let us first create a table −mysql> create table DemoTable795 ( DateOfBirth date ); Query OK, 0 rows affected (0.61 sec)Insert some records in the table using insert command −mysql> insert into DemoTable795 values('1996-01-21'); Query OK, 1 row affected (0.14 sec) mysql> insert into DemoTable795 values('2004-11-01'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable795 values('1990-03-31'); Query OK, 1 row affected (0.12 sec) mysql> insert into DemoTable795 values('2010-12-03'); Query OK, 1 row affected (0.13 sec)Display all records from the table using select ... Read More
To display number of fields in MySQL, use the COUNT(*). Following is the syntax −select COUNT(*) AS anyAliasName from INFORMATION_SCHEMA.COLUMNS where table_name = yourTableName AND TABLE_SCHEMA = yourDatabaseName;Let us first create a table −mysql> create table DemoTable794 ( ClientId int NOT NULL AUTO_INCREMENT PRIMARY KEY, ClientName varchar(100), ClientAge int, ClientCountryName varchar(100) ); Query OK, 0 rows affected (1.61 sec)Following is the query to get the number of fields in MySQL −mysql> select COUNT(*) AS TOTAL_NUMBER_OF_COLUMNS from INFORMATION_SCHEMA.COLUMNS where table_name = 'DemoTable794' AND ... Read More
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
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
Generics is a concept in Java where you can enable a class, interface and, method, accept all (reference) types as parameters. In other words it is the concept which enables the users to choose the reference type that a method, constructor of a class accepts, dynamically. By defining a class as generic you are making it type-safe i.e. it can act up on any datatype.To define a generic class you need to specify the type parameter you are using in the angle brackets “” after the class name and you can treat this as datatype of the instance variable an ... Read More
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
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
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