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You can use SUBSTRING() from MySQL to limit length of strings. The syntax is as followsSELECT SUBSTRING(yourColumnName, 1, yourIntegerValueToGetTheCharacters) as anyVariableName from yourTableName;To understand the above syntax, let us create a table. The query to create a table is as followsmysql> create table limitLengthOfLongTextDemo -> ( -> sentence LONGTEXT -> ); Query OK, 0 rows affected (0.74 sec)Insert some records in the table using insert command. The query is as followsmysql> insert into limitLengthOfLongTextDemo values('This is the introduction to MySQL'); Query OK, 1 row affected (0.17 sec) mysql> insert into ... Read More
The hashCode() method is used to obtain the hash code for a string. This method does not accept any parameters as it is a default method and it returns a hash code value.A program that demonstrates the hashCode() method in Java is given as follows:Example Live Demoimport java.io.*; public class Demo { public static void main(String args[]) { String str = new String("The sky is blue"); System.out.println("The string is: " + str); System.out.println("The Hashcode for the string is: " + str.hashCode()); } }OutputThe string is: The sky is blue The ... Read More
Both Mechanical Engineering and Electronics and Communication Engineering are equally potential branches. Both are awesome in their own way.Mech guy applies Engineering in designing and manufacturing while electric guys use their knowledge to build Electric circuits and other systems. Check for yourself, where do you belong to and do some serious research before you finalize which branch you want to opt for in your graduation.
You can use subqueries for difference between two selects in MySQL. The syntax is as follows:SELECT *FROM yourTableName where yourColumnName NOT IN(SELECT yourColumnName FROM youTableName WHERE yourCondition;To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table DifferenceSelectDemo -> ( -> Id int NOT NULL AUTO_INCREMENT, -> UserId int, -> UserValue int, -> PRIMARY KEY(Id) -> ); Query OK, 0 rows affected (0.87 sec)Insert some records in the table using insert command. The query is as follows:mysql> insert into DifferenceSelectDemo(UserId, UserValue) values(10, 10); Query ... Read More
Use DATEDIFF() function from MySQL to get the difference between two timestamps in days.The syntax is as follows −select datediff(yourColumnName1, yourColumnName2) as anyVariableName from yourTableName;To understand the above syntax, let us create a table. The following is the query to create a table −mysql> create table DifferenceTimestamp −> ( −> IssueTime timestamp, −> DueTime timestamp −> ); Query OK, 0 rows affected (0.66 sec)Insert some records in the table with the help of insert command. We are setting dates here. The query is as follows −mysql> insert into ... Read More
This error occurs when you drop a user with localhost while you have created a user with ‘%’.Let us create a user with ‘%’ and drop the user as a localhost. The syntax is as followsCREATE USER 'yourUserName'@'%' IDENTIFIED BY 'yourPassword';Let us create a user using the above syntax. The query to create a user is as followsmysql> CREATE USER 'Jack'@'%' IDENTIFIED BY '1234'; Query OK, 0 rows affected (0.26 sec)Check user is created successfully or notmysql> select user, host from MySQL.user;The following is the output+------------------+-----------+ | user | host | +------------------+-----------+ ... Read More
The HashCode for an Integer can be obtained using the hashCode() method in Java. This method does not accept any parameters and it returns a hash code value of the Integer object.A program that demonstrates the hashCode() method in Java is given as follows:Example Live Demoimport java.lang.*; public class Demo { public static void main(String args[]) { Integer i = new Integer(60); System.out.println("The integer value is: " + i); System.out.println("The Hashcode for the above value is: " + i.hashCode()); } }OutputThe integer value is: 60 The Hashcode for the above ... Read More
To understand the MySQL convert timediff output to day, hour, minute, and second format, you need to use CONCAT() from MySQL.Let us create a table. The query to create a table is as follows:mysql> create table convertTimeDifferenceDemo -> ( -> Id int NOT NULL AUTO_INCREMENT, -> StartDate datetime, -> EndDate datetime, -> PRIMARY KEY(Id) -> ); Query OK, 0 rows affected (0.68 sec)Insert some records in the table using insert command. The query to insert record is as follows:mysql> insert into convertTimeDifferenceDemo(StartDate, ... Read More
DecimalFormat is a concrete subclass of NumberFormat that formats decimal numbers.Let us set DecimalFormat(abc#) first −Format f = new DecimalFormat("'abc'#");Now, we will format a number and display the result in a string using the format() method −String res = f.format(-3968.7878);Since, we have used both Format and DecimalFormat class in Java, therefore importing the following packages in a must −import java.text.DecimalFormat; import java.text.Format;The following the complete example −Example Live Demoimport java.text.DecimalFormat; import java.text.Format; public class Demo { public static void main(String[] argv) throws Exception { Format f = new DecimalFormat("'abc'#"); ... Read More
To convert String to Long, use the valueOf() method.Let’s say the following is our string.// string String myStr = "5"; System.out.println("String: "+myStr);To convert it to Long, we have used valueOf() −Long longObj = Long.valueOf(myStr);The following is the complete example to convert a String value to Long −Example Live Demopublic class Demo { public static void main(String[] args) { // string String myStr = "5"; System.out.println("String: "+myStr); // long Long longObj = Long.valueOf(myStr); System.out.println("Converted to Long: "+longObj); } }OutputString: 5 Converted to Long: 5