Getting the full DDL of a table in Teradata is the most common requirement in order to look at the table structures. DBAs does this often to see if there is any way to improve the way the index is created. This will come in handy while debugging the performance of queries involving such tables.… Read More »
Creating a table in Teradata can be done in multiple ways. In this post, we will see how to create a table from another table without the select statement. The following examples will show how to create a table from another table in Teradata. Creating on the fly with no data This is the case… Read More »
In the other blog, we saw how to read a hive table in Spark. In this blog, we will see how to read data from Oracle This will load the data from the Oracle table to the data frame. After that, we can perform any operation as per the program needs We need to pass… Read More »
In this post, we will see how to read the data from the hive table using Spark. Spark with its in-memory computation will help to perform the data processing much faster compared to the classical Map Reduce program. The above program will get the count of a hive table and print the same Also read… Read More »
There are different modes in which we can execute a spark program. This is can be done while running the Spark-submit command to Yarn in the Hadoop cluster Mode 1 – Local In this mode, both the driver and executor program will run in the same machine. Whatever logs that are added to both the… Read More »
In this post, we will see how to establish a passwordless SSH connection between two Linux machines. This can be done by using the Public and Private keys. Once the keys are set up, the authentication will be done using these keys instead of the password. Let us consider there are two Linux machines/servers ServerA… Read More »
In this blog, we will see how to archive/delete a file in HDFS if it is n days older. We can use this to check for any number of days. For example, let us say that we need to monitor an HDFS folder and delete the files when they become 7 days older.
In Python, we can merge two dictionary objects very easily. First, we create two dictionaries then we can merge and sort the dictionaries based on the values. In python 2.x we can use the following code, Python 2.x In the below example, the two dictionaries are created and then merge the dictionary keys with the… Read More »
In the following code, we are assigning default values to the dictionary. First, we can create the dictionary and assigning the values to the names. Then, we are trying to fetch the dictionary value based on the key. If there is no such key, we will assign a default value.
Let us take a real-time example of the banking system. The bank wants to offer a loan only to the active premium customers who are not on the defaulter’s list. For this, we are using the following code in python. Method: 1 Method: 2 In this example, if the bank gives a loan to the… Read More »