0) Database manage karna matlab kya?

DB manage karna = server pe:

• database create karna
• database select/switch karna
• database delete/drop karna
• databases/tables ki list dekhna

Yeh sab DDL category me aata hai (structure/admin work).

1) CREATE DATABASE IF NOT EXISTS db_name;

Kya karta hai?

• Server ke andar ek naya database container create karta hai.
• Database = tables, views, procedures, etc. ka “folder-like namespace”.

Syntax

CREATE DATABASE IF NOT EXISTS mydb;

IF NOT EXISTS ka benefit

• Agar mydb already exists hai, to error nahi aayega.
• Command safe ho jata hai for scripts/automation.

Without IF NOT EXISTS

CREATE DATABASE mydb;

Agar exist karta hai: error.