HBASE Vs. RDBMS Top Differences You can Unlock Now

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HBASE in the Big data context has a lot of benefits over RDBMS. The listed differences below make you understandable why HBASE is popular in Hadoop (or Bigdata) platform. Let us check one by one quickly. HBASE Vs. RDBMS Differences Random Accessing HBase handles a large amount of data that is store in a distributed manner in the column-oriented format while RDBMS is systematic storage of a database that cannot support a random manner for accessing the database. Database Rules RDBMS strictly follow Codd's 12 rules with fixed schemas and row-oriented manner of database and also follow ACID properties. HBase follows BASE properties and implement complex queries. Secondary indexes, complex inner and outer joins, count, sum, sort, group, and data of page and table can easily be accessible by RDBMS. Storage From small to medium storage application there is the use of RDBMS that provide the solution with MySQL and PostgreSQL whose size increase with concurrency and performance.  Codd'

SQL Tester Ideas DATE, Numeric, CHAR, NULL

I have shared top SQL Date functions along with Numeric, CHAR and NULL functions.


sql examples on built-in functions


List of Built-in Functions

  1. DATE-TIME functions
  2. Numeric functions
  3. Char functions
  4. Null-related functions

1. DATE/TIME functions

SELECT p_code,
launch_dt,
CURRENT_DATE
FROM product;

CURRENT_DATE returns the CURRENT date.

SELECT p_code,
To_char(launch_dt, 'DD MONTH YYYY') reformatted_dt
FROM product;
TO_CHAR FUNCTION returns date IN char format.

2. Numeric functions

SELECT p_code,
price,
(price - 20),
Abs(price - 20.00)
FROM product;


ABS - FUNCTION returns the absolute value


SELECT p_code,
price,
Round (price, 1)
FROM product;


ROUND FUNCTION - round TO 1 digit.


SELECT p_code,
price,
Sign(price - 15)
FROM product;


SIGN FUNCTION - it returns the sign

SELECT p_code,
price,
Trunc(price, 1)
FROM product;


TRUNC FUNCTION - truncates TO a certain number OF decimal places.


3. CHAR functions

SELECT p_code,
Concat(Concat(p_name, ' -- ') , price)
FROM product;CONCAT FUNCTION - concats two strings.




SELECT p_name,
Lower(p_name),
Upper(p_name)
FROM product;


UPPER FUNCTION : returns upper CASE.
Lower FUNCTION returns lower CASE.




SELECT p_name,
Length(p_name)
FROM product;LENGTH FUNCTION
returns length OF the string.


SELECT Substr(phone, 3)

FROM customer;


SUBSTR FUNCTION : returns a substring FROM the main string.


4. Null related functions

SELECT p_name,
price,
min_price,
COALESCE((price * 0.9), min_price, 5.0) sale_price
FROM product;


COALESCE FUNCTION: returns the first non-NULL value FROM the expression.



Summary
  • Given a list of top built-in functions
  • Example SQL queries on built-in function given for you to read quickly
  • These examples are almost common in any RDBMS

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