IBM Interview Questions and Answers

Bucketing is a way of organizing data files into multiple files based on a hash function, while partitioning is dividing data into different directories based on the column values.

• Bucketing is used for evenly distributing data across files for better query performance.

• Partitioning is used for organizing data based on specific column values for easier data retrieval.

• Example: Bucketing can be used to evenly distribute sales data into 4 files, while partitioning can organize the...read more

Hive tables are used to store structured data in Hive, similar to tables in a traditional database.

• Hive tables are created using the CREATE TABLE statement.

• Tables can be partitioned based on one or more columns.

• External tables in Hive store data outside of the default location in HDFS.

• Managed tables store data in the default location in HDFS.

• Tables can be queried using SQL-like syntax in HiveQL.

Types of read mode in Spark include permissive, dropMalformed, and failFast.

• Permissive mode - ignores corrupted records and loads all possible data

• DropMalformed mode - drops corrupted records during reading

• FailFast mode - fails immediately upon encountering corrupted records

JDK is a development kit, JRE is a runtime environment, and JVM is a virtual machine that executes Java bytecode.

• JDK (Java Development Kit) is a software development kit used to develop Java applications.

• JRE (Java Runtime Environment) is a software package that provides the libraries and components necessary for running Java applications.

• JVM (Java Virtual Machine) is an abstract machine that provides the runtime environment in which Java bytecode can be executed.

• JDK includes ...read more

JVM GC manages memory by reclaiming unused objects, improving performance.

• JVM GC stands for Java Virtual Machine Garbage Collection

• It automatically manages memory by reclaiming unused objects

• Different types of GC algorithms like Serial, Parallel, CMS, G1 are available

• GC can cause pauses in application execution, affecting performance

Generics in Kotlin allow you to write flexible and reusable code by defining classes, functions, and interfaces with type parameters.

• Generics in Kotlin are defined using angle brackets <> after the class name or function name.

• You can specify the type parameter when creating an instance of a generic class or calling a generic function.

• Generics help in writing type-safe code and avoid the need for casting.

• Example: List is a generic type representing a list of strings.