7

 hive

CREATE DATABASE employee_db;

USE employee_db;

CREATE TABLE employees (

    emp_id INT,

    name STRING,

    age INT,

    dept_id INT,

    salary FLOAT

)

ROW FORMAT DELIMITED

FIELDS TERMINATED BY ','

STORED AS TEXTFILE;

LOAD DATA INPATH '/user/cloudera/employees.txt' INTO TABLE employees;

ALTER TABLE employees ADD COLUMNS (email STRING);

ALTER TABLE employees RENAME TO employees_new;

DROP TABLE employees_new;

CREATE VIEW high_salary_employees AS

SELECT emp_id, name, salary FROM employees WHERE salary > 50000;


ALTER VIEW high_salary_employees AS

SELECT emp_id, name, age, salary FROM employees WHERE salary > 60000;

DROP VIEW high_salary_employees;

SHOW TABLES;

DESCRIBE employees;

SELECT * FROM employees LIMIT 5;

-=








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