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SQL Interview Success: Unlocking the Top 5 Frequently Asked Queries

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 Here are the five top commonly asked SQL queries in the interviews. These you can expect in Data Analyst, or, Data Engineer interviews. Top SQL Queries for Interviews 01. Joins The commonly asked question pertains to providing two tables, determining the number of rows that will return on various join types, and the resultant. Table1 -------- id ---- 1 1 2 3 Table2 -------- id ---- 1 3 1 NULL Output ------- Inner join --------------- 5 rows will return The result will be: =============== 1  1 1   1 1   1 1    1 3    3 02. Substring and Concat Here, we need to write an SQL query to make the upper case of the first letter and the small case of the remaining letter. Table1 ------ ename ===== raJu venKat kRIshna Solution: ========== SELECT CONCAT(UPPER(SUBSTRING(name, 1, 1)), LOWER(SUBSTRING(name, 2))) AS capitalized_name FROM Table1; 03. Case statement SQL Query ========= SELECT Code1, Code2,      CASE         WHEN Code1 = 'A' AND Code2 = 'AA' THEN "A" | "A
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Big Data: Top NoSQL Interview Questions (2 of 5)

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Oracle+NoSQL+JOBS
1) What is most important character of NoSQL?
High Availability

2)Different types of NoSQL databases?
Key-Value stores
Column Stores
Graph Stores
Document Stores

3)What is oracle NoSQL database?
Oracle NoSQL Database is a distributed key-value database designed to provide highly reliable, scalable, and available data storage across a configurable set of systems.

4)What is the DB engine being used in Oracle NoSQL database?
Oracle NoSQL Database uses Oracle Berkeley DB Java Edition as the underlying data storage engine.

5)What is oracle NoSQL database?
Oracle NoSQL Database is a shared-nothing system designed to run and scale on commodity hardware. Key-value pairs are hash partitioned across server groups known as shards. At any point in time, a single key-value pair is always associated with a unique shard in the system.

6) What are unique features of Oracle NoSQL?
Oracle NoSQL Database leverages the high availability features in Berkeley DB in order to provide resiliency, fault tolerance, and read scalability.

7)What is the concept of shared nothing in Oracle NoSQL database?
A shared-nothing system partitions the data into disjoint subsets (called shards), each shard managed by a node (along with replicas for providing high availability).

8) How oracle NoSQL acheives high availablity?
Availability is achieved by adding redundancy to the system. In NoSQL systems, redundancy is commonly achieved by maintaining multiple copies of the data on multiple nodes. Each shard comprises two or more nodes (called replicas) that have identical copies of the data.

9) What is ACID in Oracle NoSQL?
Atomicity, consistency, isolation, and durability (ACID) are the key characteristics provided by transactions. Oracle NoSQL Database leverages the transaction capabilities of the underlying Berkeley DB storage engine.

10)How data will be modeled in No SQL Database?
Oracle NoSQL Database provides a key-value paradigm to the application developer. Every entity (record) is a set of key-value pairs. A key has multiple components, specified as an ordered list. The major key identifies the entity and consists of the leading components of the key. The subsequent components are called minor keys.
This organization is similar to a directory path specification in a file system (for example, /Major/minor1/minor2/). The "value" part of the key-value pair is simply an uninterpreted string of bytes of arbitrary length.

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