SQL

Different Database Options

Commands	Purpose
PRAGMA table_info(<table_name>)
sql<br>SELECT ... <br>FROM ...<br>EXCEPT<br> ...<br>

Commands (for Hive)	Purpose
CREATE TABLE ...
CREATE TABLE IF NOT EXISTS ...
DROP TABLE ...
CREATE OR REPLACE TABLE ...
ALTER TABLE ... RENAME TO ...
ALTER TABLE ... SET LOCATION
DESCRIBE
DESCRIBE FORMATTED
ALTER TABLE ... DROP PARITION ...
ALTER TABLE ... ADD PARTITION ...
SHOW PARTITIONS

PostgreSQL Commands

List all tables in a specific schema

SELECT table_name 
FROM information_schema.tables 
WHERE table_schema = 'public';

List all tables with their schemas

SELECT table_schema, table_name 
FROM information_schema.tables 
WHERE table_schema NOT IN ('information_schema', 'pg_catalog')
ORDER BY table_schema, table_name;

Get column details for a specific table:

SELECT 
    column_name,
    data_type,
    is_nullable,
    column_default,
    character_maximum_length
FROM information_schema.columns 
WHERE table_schema = 'public' 
AND table_name = 'your_table_name'
ORDER BY ordinal_position;

Get all columns from all tables

SELECT 
    table_schema,
    table_name,
    column_name,
    data_type,
    is_nullable
FROM information_schema.columns 
WHERE table_schema NOT IN ('information_schema', 'pg_catalog')
ORDER BY table_schema, table_name, ordinal_position;