#Transdata database code

createIndex (new BasicDBObject ('Customer_Id', 1)) Īfter Customer_Id has been defined as an index, it is possible to find all transactions for a customer as shown in the following code snippet. This can be achieved by making it an index as follows. To find all transactions for a particular customer, it is necessary to be able to search by Customer_Id. Statement D also creates the collection if it did not exist previously. This is then inserted into the transactionData collection by statement D. Statement B creates an empty object, which is populated in statement C with the fields of the transaction shown earlier. Statement A gets a pointer to the transactionData collection if it already exists otherwise it creates a pending pointer. It is not necessary in MongoDB to explicitly create the collection the collection is created the first time an object is inserted into the collection (assuming that a connection to the database has already been initialized as in the previous example). It is assumed that the transaction data is in a collection called transactionData in the database db.ĭBCollection transData = dbConn.getCollection('transactionData') // AīasicDBObject trans = new BasicDBObject() // B

The next snippet shows the statements needed to insert a new transaction into the transaction data. Note that it is not necessary in MongoDB to explicitly create a database the database is created the first time a client connects to it. Statement A connects to a MongoDB database server and statement B connects to a database on the server. Mongo connPool = new Mongo ('transDB', 27017) // A The following code is a simple example of the set of statements needed to connect to a MongoDB database. The cases of inserting a transaction into the transaction table, and getting all transactions for a customer will be considered. In the rest of this section, methods of programming MongoDB are considered. Dinkar Sitaram, Geetha Manjunath, in Moving To The Cloud, 2012 MongoDB programming

Transdata database