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Articles by Chandu yadav
Page 58 of 81
Query MongoDB for a datetime value less than NOW?
You can use $lte operator along with new Date() for this. Let us first create a collection with documents>db.dateTimeValueLessThanNowDemo.insertOne({"CustomerName":"Larry", "CustomerProductName":"Product-1", "ArrivalDate":new ISODate("2017-01-31")}); { "acknowledged" : true, "insertedId" : ObjectId("5ca1e8ab66324ffac2a7dc59") } >db.dateTimeValueLessThanNowDemo.insertOne({"CustomerName":"Mike", "CustomerProductName":"Product-2", "ArrivalDate":new ISODate("2019-04-01")}); { "acknowledged" : true, "insertedId" : ObjectId("5ca1e8c166324ffac2a7dc5a") } >db.dateTimeValueLessThanNowDemo.insertOne({"CustomerName":"Chris", "CustomerProductName":"Product-3", "ArrivalDate":new ISODate("2019-03-31")}); { "acknowledged" : true, "insertedId" : ObjectId("5ca1e8d266324ffac2a7dc5b") } >db.dateTimeValueLessThanNowDemo.insertOne({"CustomerName":"Robert", "CustomerProductName":"Product-4", "ArrivalDate":new ISODate("2019-04-02")}); { "acknowledged" : true, "insertedId" : ObjectId("5ca1e8e766324ffac2a7dc5c") }Following is the query to display all documents from a collection with the help of find() method> db.dateTimeValueLessThanNowDemo.find().pretty();This will produce the following output{ "_id" : ObjectId("5ca1e8c166324ffac2a7dc5a"), ...
Read More8086 program to subtract two 16 bit BCD numbers
In this program we will see how to subtract two 16-bit BCD numbers.Problem StatementWrite 8086 Assembly language program to subtract two 16-bit BCD numbers stored in memory offset 500H – 501H and 502H – 503H.DiscussionHere we are adding the 16-bit data byte by byte. At first we are subtracting lower byte and perform the DAS instruction, then Subtract higher bytes with borrow, and again DAS to adjust. The final result is stored at location offset 600H, and if borrow is present, it will be stored at 601H.We are taking two numbers 8523 - 7496 = 1027InputAddressData……50023501855029650374…… Flow Diagram Program OutputAddressData……600276011060200……
Read MoreSet Ennead value in JavaTuples
To set Ennead value in Java, you need to use the setAtX() method. Here, X represents the index wherein you need to set the value i.e. for index 1, use setAt1() method. Set the value as the parameter value of the method.Let us first see what we need to work with JavaTuples. To work with Ennead class in JavaTuples, you need to import the following packageimport org.javatuples.Ennead;Note Download JavaTuples Jar library to run JavaTuples program. If you are using Eclipse IDE, then Right Click Project -> Properties -> Java Build Path -> Add External Jars and upload the downloaded JavaTuples ...
Read MoreUsing find() to search for nested keys in MongoDB?
For find() to search for nested keys in MongoDB, you can use dot(.) notation. Following is the syntaxdb.yourCollectionName.find({"yourOuterFieldName.yourInnerFieldName":"yourValue"}).pretty();Let us first create a collection with documents:>db.searchForNestedKeysDemo.insertOne({"ClientName":"Larry", "ClientAge":28, "ClientExtra Details":{"isEducated":true, "CountryName":"US"}}); { "acknowledged" : true, "insertedId" : ObjectId("5ca20e8b66324ffac2a7dc64") } >db.searchForNestedKeysDemo.insertOne({"ClientName":"Chris", "ClientAge":29, "ClientExtra Details":{"isEducated":false, "CountryName":"UK"}}); { "acknowledged" : true, "insertedId" : ObjectId("5ca20ea366324ffac2a7dc65") } >db.searchForNestedKeysDemo.insertOne({"ClientName":"David", "ClientAge":39, "ClientExtra Details":{"isEducated":true, "CountryName":"AUS"}}); { "acknowledged" : true, "insertedId" : ObjectId("5ca20eba66324ffac2a7dc66") }Following is the query to display all documents from a collection with the help of find() method> db.searchForNestedKeysDemo.find().pretty();This will produce the following output{ "_id" : ObjectId("5ca20e8b66324ffac2a7dc64"), "ClientName" : "Larry", ...
Read MoreIs there a way to convert Integer field into Varchar without losing data in MySQL?
You can use ALTER command to convert Integer into Varchar. Let us first create a tablemysql> create table DemoTable ( UserId int, UserFirstName varchar(20), UserLastName varchar(20), UserAge int ); Query OK, 0 rows affected (0.73 sec)Now check the description of table using DESC command:mysql> desc DemoTable;This will produce the following output −+---------------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +---------------+-------------+------+-----+---------+-------+ | UserId | int(11) | YES | | NULL | ...
Read MoreMySQL appears to DROP USER but user still exists in MySQL.users table?
First check all the user and host from MySQL.user table with the help of select statement as shown belowmysql> select user, host from MySQL.user;The following is the output+------------------+-----------+ | user | host | +------------------+-----------+ | Bob | % | | Manish | % | | User2 | % | | mysql.infoschema | % | | mysql.session | % ...
Read More8086 program to divide a 16 bit number by an 8 bit number
In this program we will see how to divide 16-bit number by an 8-bit number.Problem StatementWrite 8086 Assembly language program to divide 16-bit number stored in memory location offset 501. Divide it with 8-bit number stored in 500H. Also store result at memory offset 600.Discussiont8086 has DIV instruction to perform division. Take the 8-bit number into BL, and 16-bit number into AX. Now divide AX by BL. The result will be stored at AX.We are taking two numbers 24CF / 2D = D1InputAddressData……5002D501CF50224…… Flow Diagram Program OutputAddressData……600D1……
Read MoreHow do I find all documents with a field that is NaN in MongoDB?
To find all documents with a field that is NAN in MongoDB, use the following syntaxdb.yourCollectionName.find( { yourFieldName: NaN })Let us first create a collection with documents> db.nanDemo.insertOne({"Score":0/0}); { "acknowledged" : true, "insertedId" : ObjectId("5ca251a26304881c5ce84b8a") } > db.nanDemo.insertOne({"Score":10/5}); { "acknowledged" : true, "insertedId" : ObjectId("5ca2520e6304881c5ce84b8b") } > db.nanDemo.insertOne({"Score":20/0}); { "acknowledged" : true, "insertedId" : ObjectId("5ca252156304881c5ce84b8c") } > db.nanDemo.insertOne({"Score":0/20}); { "acknowledged" : true, "insertedId" : ObjectId("5ca2521e6304881c5ce84b8d") }Following is the query to display all documents from a collection with the help of find() method> db.nanDemo.find().pretty();This will produce the following output{ "_id" : ObjectId("5ca251a26304881c5ce84b8a"), "Score" ...
Read MoreHow to handle error object in JSP using JSTL tags?
You can make use of JSTL tags to write an error page ShowError.jsp with better structure and more information − Show Error Page Opps... Error: ${pageContext.exception} URI: ${pageContext.errorData.requestURI} ...
Read MoreMySQL query to calculate the average of values in a row?
To calculate the average of values in a row in MySQL, use the following syntaxSELECT (yourTableName.yourColumnName1+yourTableName.yourColumnName2+yourTableName.yourColumnName3+, ..........N)/numberOfColumns AS anyAliasName FROM yourTableName;To understand the above syntax, let us create a table. The query to create a table is as followsmysql> create table calculateAverageDemo -> ( -> x int, -> y int, -> z int -> ); Query OK, 0 rows affected (1.41 sec)Insert some records in the table using insert command.The query is as followsmysql> insert into calculateAverageDemo values(10, 20, 30); Query OK, 1 row affected (0.78 sec) mysql> insert into calculateAverageDemo values(40, 50, 70); Query ...
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