Implementation:Heibaiying BigData Notes Hive Create Database

Knowledge Sources	BigData-Notes Hive Language Manual
Domains	Data_Warehouse, Big_Data
Last Updated	2026-02-10 10:00 GMT

Overview

Concrete tool for creating, selecting, listing, and dropping Hive databases provided by Apache Hive.

Description

Hive database DDL statements allow users to create logical namespaces that organize tables, views, and other schema objects. Each database maps to a directory on HDFS under the Hive warehouse path. The CREATE DATABASE statement provisions the namespace and its HDFS directory, USE switches the active database context, SHOW DATABASES lists all available databases, and DROP DATABASE removes a database and optionally all its contents.

These operations are executed as HiveQL statements through the Hive CLI, Beeline client, or any JDBC/ODBC-connected tool. They are metadata-only operations (except DROP CASCADE, which also removes HDFS data for managed tables).

Usage

Use these statements to set up and manage the top-level organizational structure of a Hive data warehouse. Typical scenarios include initializing project databases during environment setup, switching contexts in multi-database scripts, and cleaning up deprecated databases.

Code Reference

Source Location

• Repository: BigData-Notes
• File: notes/Hive常用DDL操作.md (Lines 1-453)

Signature

-- Create a database
CREATE DATABASE [IF NOT EXISTS] db_name
  [COMMENT 'description']
  [LOCATION 'hdfs_path']
  [WITH DBPROPERTIES (key='value', ...)];

-- Switch to a database
USE db_name;

-- Drop a database
DROP DATABASE [IF EXISTS] db_name [RESTRICT | CASCADE];

-- List databases
SHOW DATABASES [LIKE 'pattern'];

Import

N/A (HiveQL statements executed via Hive CLI or Beeline)

I/O Contract

Inputs

Name	Type	Required	Description
db_name	STRING	Yes	Name of the database to create, use, or drop
COMMENT	STRING	No	Human-readable description stored in the metastore
LOCATION	STRING (HDFS path)	No	Custom HDFS directory path for the database; defaults to /user/hive/warehouse/db_name.db
DBPROPERTIES	MAP<STRING, STRING>	No	Key-value metadata properties associated with the database
CASCADE	Keyword	No	When dropping, removes all tables and data within the database first
LIKE pattern	STRING	No	Glob pattern to filter database names when listing (e.g., 'sales_*')

Outputs

Name	Type	Description
Database directory	HDFS directory	Created at the specified or default HDFS location upon CREATE DATABASE
Metastore entry	Metadata	Database registration in the Hive metastore including name, comment, location, and properties
Database list	Result set	Output of SHOW DATABASES listing matching database names

Usage Examples

-- Create a database with a comment and custom location
CREATE DATABASE IF NOT EXISTS sales_dw
  COMMENT 'Sales data warehouse'
  LOCATION '/data/warehouse/sales_dw'
  WITH DBPROPERTIES ('owner'='data_team', 'env'='production');

-- List all databases matching a pattern
SHOW DATABASES LIKE 'sales_*';

-- Switch to the new database
USE sales_dw;

-- Verify the current database context by showing tables
SHOW TABLES;

-- Drop the database and all its contents
DROP DATABASE IF EXISTS sales_dw CASCADE;

Related Pages

Implements Principle

• Principle:Heibaiying_BigData_Notes_Hive_Database_Creation