This SHOW DBS command won’t show the databases because you may have not created a document for a collection. If you will create document for a collection then the created database will be visible.Let us implement the above concept and create a database −> use web; switched to db webFollowing ... Read More

The max_heap_table_size is a system variable that has both read/write property.Initially, max_heap_table_size has size 16 MB. First, check the value of max_heap_table_size, which is in bytes.The query is as follows −mysql> select @@max_heap_table_size;The following is the output −+-----------------------+ | @@max_heap_table_size | +-----------------------+ | 16777216 ... Read More

Let’s say we have the following two dates −LocalDate.of(2019, 3, 20); LocalDate.of(2019, 10, 25);To get the number of quarters between the above two dates, use the QUARTER_YEARS −IsoFields.QUARTER_YEARS.between(LocalDate.of(2019, 3, 20), LocalDate.of(2019, 10, 25));Exampleimport java.time.LocalDate; import java.time.temporal.IsoFields; public class Demo {    public static void main(String[] args) {       ... Read More

You can use $or operator for this. Let us first create a collection with documents −> db.applyConditionDemo.insertOne({"StudentName":"Larry", "StudentAge":21, "StudentMarks":45}); {    "acknowledged" : true,    "insertedId" : ObjectId("5cb80b78623186894665ae36") } > db.applyConditionDemo.insertOne({"StudentName":"Sam", "StudentAge":23, "StudentMarks":55}); {    "acknowledged" : true,    "insertedId" : ObjectId("5cb80b87623186894665ae37") } > db.applyConditionDemo.insertOne({"StudentName":"David", "StudentAge":21, "StudentMarks":65}); {    "acknowledged" ... Read More

Cookies are usually set in an HTTP header (although JavaScript can also set a cookie directly on a browser). A JSP that sets a cookie might send headers that look something like this −HTTP/1.1 200 OK Date: Fri, 04 Feb 2000 21:03:38 GMT Server: Apache/1.3.9 (UNIX) PHP/4.0b3 Set-Cookie: name = ... Read More

You can achieve this with the help of INFORMATION_SCHEMA.COLUMNS. The syntax is as follows −SELECT CONCAT('ALTER TABLE ', TABLE_NAME, ' CHANGE `', COLUMN_NAME, '` `', LOWER(COLUMN_NAME), '` ', COLUMN_TYPE, ';') AS anyAliasName FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = ‘yourDatabaseName’;Now use the database which has two tables. The database name is as ... Read More

The current instance of the clock with the UTC time zone can be obtained using the method systemUTC() in the Clock Class in Java. This method requires no parameters and it returns the current instance of the clock with the UTC time zone.A program that demonstrates this is given as ... Read More

Let us create Unit Tuple in Java using with() method.Let us first see what we need to work with JavaTuples. To work with the Unit class in JavaTuples, you need to import the following package −import org.javatuples.Unit;Note − Steps to download and run JavaTuples program If you are using Eclipse ... Read More

To read cookies, you need to create an array of javax.servlet.http.Cookie objects by calling the getCookies( ) method of HttpServletRequest. Then cycle through the array, and use getName() and getValue() methods to access each cookie and associated value.Let us now read cookies that were set in the previous example −Example Live ... Read More

You can also create a Pair Tule in Java using the with() method.Let us first see what we need to work with JavaTuples. To work with Pair class in JavaTuples, you need to import the following package −import org.javatuples.Pair;Note − Steps to download and run JavaTuples program If you are ... Read More