To know the biggest value from two or more fields, use the function GREATEST() from MySQL.The syntax is as follows −SELECT GREATEST(MAX(yourColumnName1), MAX(yourColumnName2), ...............MAX(yourColumnName2) ) from yourTableName;Let us understand the above concept by creating a table with more than two columns −mysql> create table GreatestOfTwoOrMore -> ( ... Read More

Yes, you can use the method CURRENT_USER() to know the current username in MySQL.The above method returns the username that can be used to authenticate the client connection.The query is as follows −mysql> select CURRENT_USER();The following is the output −+----------------+ | CURRENT_USER() | +----------------+ | root@% ... Read More

Some situations, we have to restrict an edit text for some characters. To solve this situation, in this example demonstrate how to Counting Chars in Edit Text Changed Listener.Step 1 - Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to ... Read More

To change the default charset of a MySQL table, you can use the below syntax. The syntax is as follows −alter table yourTableName convert to character set yourCharsetName;Let us create a table and apply the above syntax to change the default charset. The query to create a table −mysql> create ... Read More

Use Iterator class to fetch elements of TreeSet.Create a TreeSet and add elements to itTreeSet set = new TreeSet(); set.add("13"); set.add("11"); set.add("12"); set.add("16"); set.add("19"); set.add("23"); set.add("21"); set.add("20"); set.add("30");Now, to display the elements, use Iterator classIterator i = set.iterator(); while(i.hasNext()){ System.out.println(i.next()); }The following is an example that fetch ... Read More

To convert string to date in MySQL, you can use STR_TO_DATE() function. The syntax is as follows −select str_to_date(‘StringValue’, '%d, %m, %Y') as anyVariableName;Apply the above syntax in the following query wherein, we have a string value −mysql> SELECT STR_TO_DATE('26, 11, 2018', '%d, %m, %Y');The following is the output −+--------------------------------------+ ... Read More

The pollFirstEntry() method in NavigableMap remove and return a key-value mapping associated with the least key in this mapThe following is an example to implement pollFirstEntry() methodExample Live Demoimport java.util.*; public class Demo { public static void main(String[] args) { NavigableMap n ... Read More

To remove all values from HashMap, use the clear() method.First, let us create a HashMap.HashMap hm = new HashMap();Add some elements to the HashMaphm.put("Wallet", new Integer(700)); hm.put("Belt", new Integer(600)); hm.put("Backpack", new Integer(1200));Now, remove all the elementshm.clear();The following is an example to remove all values from HashMap.Example Live Demoimport java.util.*; public class ... Read More

To know where MySQL store database files, you can use the variable @@datadir. The query is as follows −mysql> select @@datadir;The following is the output that displays the path −+---------------------------------------------+ | @@datadir ... Read More

To add 30 days to a value in the table, you can use ADDDATE() function with UPDATE command. The syntax is as follows:UPDATE yourTableName SET yourDateColumnName=ADDDATE(yourDateColumnName, INTERVAL 30 DAY);To understand the above syntax, let us create a table. The query to create a table is as follows:mysql> create table Add30DayDemo ... Read More