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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>PostgreSQL Guide — DevDunia Comics</title>
<meta name="description" content="Complete PostgreSQL reference guide with commands, functions, and examples. Essential PostgreSQL documentation for developers.">
<meta property="og:type" content="website">
<meta property="og:url" content="https://devdunia.com/production/postgresql-guide.html">
<meta property="og:title" content="PostgreSQL Guide — DevDunia Comics">
<meta property="og:description" content="Complete PostgreSQL reference with commands, functions, and practical examples.">
<meta property="og:image" content="https://devdunia.com/images/logo.png">
<link rel="preconnect" href="https://fonts.googleapis.com">
<link href="https://fonts.googleapis.com/css2?family=Bangers&family=Comic+Neue:wght@400;700&family=Space+Mono:wght@400;700&display=swap" rel="stylesheet">
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max-width: 1240px; margin: 0 auto;
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/* Search */
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<body>
<div class="paper-overlay"></div>
<div class="copied-flash" id="copied-flash">✔ COPIED!</div>
<div data-masthead></div>
<div class="page-wrap">
<!-- MASTHEAD -->
<div data-tool-hero
data-title="PostgreSQL Guide"
data-chapter="02"
data-category="Database"
data-icon="🐘"
data-desc="Comprehensive PostgreSQL reference — queries, indexes, joins, transactions, performance and common patterns."
data-color="blue"
data-badges="POSTGRES,SQL,REFERENCE,FREE"
data-badge-colors="blue,orange,green,yellow">
</div>
<!-- SEARCH -->
<div class="search-panel">
<input type="text" id="searchInput" class="search-input" placeholder="Search PostgreSQL commands, functions, or concepts...">
</div>
<!-- DATABASE MANAGEMENT -->
<div class="panel command-section" id="section-db">
<div class="panel-header">
🗄️ DATABASE MANAGEMENT
<span class="panel-tag">DDL</span>
</div>
<div class="panel-body">
<div class="grid-2">
<div class="cmd-card">
<h3 class="blue">Create Database</h3>
<div class="syntax-box" onclick="copyEl(this)">CREATE DATABASE database_name;</div>
<p class="cmd-desc">Creates a new database with the specified name.</p>
<div class="example-box" onclick="copyEl(this)">-- Example
CREATE DATABASE myapp;
CREATE DATABASE test_db WITH ENCODING 'UTF8';</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="red">Drop Database</h3>
<div class="syntax-box" onclick="copyEl(this)">DROP DATABASE database_name;</div>
<p class="cmd-desc">Permanently deletes a database and all its data.</p>
<div class="example-box" onclick="copyEl(this)">-- Example
DROP DATABASE old_db;
DROP DATABASE IF EXISTS temp_db;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="cyan">Connect to Database</h3>
<div class="syntax-box" onclick="copyEl(this)">\c database_name</div>
<p class="cmd-desc">Connects to a specific database in psql.</p>
<div class="example-box" onclick="copyEl(this)">-- Example
\c myapp
\c postgres</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="yellow">List Databases</h3>
<div class="syntax-box" onclick="copyEl(this)">\l</div>
<p class="cmd-desc">Lists all databases in the PostgreSQL server.</p>
<div class="example-box" onclick="copyEl(this)">-- Alternative
SELECT datname FROM pg_database;</div>
<div class="click-hint">click to copy</div>
</div>
</div>
</div>
</div>
<!-- TABLE OPERATIONS -->
<div class="panel command-section" id="section-tables">
<div class="panel-header">
📋 TABLE OPERATIONS
<span class="panel-tag">TABLES</span>
</div>
<div class="panel-body">
<div class="grid-2">
<div class="cmd-card">
<h3 class="green">Create Table</h3>
<div class="syntax-box" onclick="copyEl(this)">CREATE TABLE table_name (column_definitions);</div>
<p class="cmd-desc">Creates a new table with specified columns and constraints.</p>
<div class="example-box" onclick="copyEl(this)">CREATE TABLE users (
id SERIAL PRIMARY KEY,
name VARCHAR(100) NOT NULL,
email VARCHAR(255) UNIQUE,
created_at TIMESTAMP DEFAULT NOW()
);</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="red">Drop Table</h3>
<div class="syntax-box" onclick="copyEl(this)">DROP TABLE table_name;</div>
<p class="cmd-desc">Permanently deletes a table and all its data.</p>
<div class="example-box" onclick="copyEl(this)">-- Example
DROP TABLE old_table;
DROP TABLE IF EXISTS temp_table;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="blue">Alter Table</h3>
<div class="syntax-box" onclick="copyEl(this)">ALTER TABLE table_name action;</div>
<p class="cmd-desc">Modifies the structure of an existing table.</p>
<div class="example-box" onclick="copyEl(this)">-- Add column
ALTER TABLE users ADD COLUMN age INTEGER;
-- Drop column
ALTER TABLE users DROP COLUMN age;
-- Rename column
ALTER TABLE users RENAME COLUMN name TO full_name;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="yellow">List Tables</h3>
<div class="syntax-box" onclick="copyEl(this)">\dt</div>
<p class="cmd-desc">Lists all tables in the current database.</p>
<div class="example-box" onclick="copyEl(this)">-- Alternative
SELECT table_name FROM information_schema.tables
WHERE table_schema = 'public';</div>
<div class="click-hint">click to copy</div>
</div>
</div>
</div>
</div>
<!-- DATA MANIPULATION (DML) -->
<div class="panel command-section" id="section-dml">
<div class="panel-header">
💾 DATA MANIPULATION (DML)
<span class="panel-tag">DML</span>
</div>
<div class="panel-body">
<div class="grid-2">
<div class="cmd-card">
<h3 class="green">INSERT</h3>
<div class="syntax-box" onclick="copyEl(this)">INSERT INTO table_name VALUES (values);</div>
<p class="cmd-desc">Inserts new rows into a table.</p>
<div class="example-box" onclick="copyEl(this)">-- Single row
INSERT INTO users (name, email) VALUES ('John', 'john@example.com');
-- Multiple rows
INSERT INTO users (name, email) VALUES
('Alice', 'alice@example.com'),
('Bob', 'bob@example.com');</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="blue">SELECT</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT columns FROM table_name WHERE condition;</div>
<p class="cmd-desc">Retrieves data from one or more tables.</p>
<div class="example-box" onclick="copyEl(this)">-- All columns
SELECT * FROM users;
-- Specific columns
SELECT name, email FROM users WHERE age > 18;
-- With ordering
SELECT * FROM users ORDER BY created_at DESC;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="yellow">UPDATE</h3>
<div class="syntax-box" onclick="copyEl(this)">UPDATE table_name SET column = value WHERE condition;</div>
<p class="cmd-desc">Modifies existing rows in a table.</p>
<div class="example-box" onclick="copyEl(this)">-- Update single row
UPDATE users SET email = 'new@example.com' WHERE id = 1;
-- Update multiple columns
UPDATE users SET name = 'John Doe', age = 30 WHERE id = 1;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="red">DELETE</h3>
<div class="syntax-box" onclick="copyEl(this)">DELETE FROM table_name WHERE condition;</div>
<p class="cmd-desc">Removes rows from a table.</p>
<div class="example-box" onclick="copyEl(this)">-- Delete specific row
DELETE FROM users WHERE id = 1;
-- Delete with condition
DELETE FROM users WHERE created_at < '2023-01-01';</div>
<div class="click-hint">click to copy</div>
</div>
</div>
</div>
</div>
<!-- JOINS -->
<div class="panel command-section" id="section-joins">
<div class="panel-header">
🔗 JOINS
<span class="panel-tag">JOINS</span>
</div>
<div class="panel-body">
<div class="grid-2">
<div class="cmd-card">
<h3 class="orange">INNER JOIN</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT * FROM table1 INNER JOIN table2 ON condition;</div>
<p class="cmd-desc">Returns only matching rows from both tables.</p>
<div class="example-box" onclick="copyEl(this)">SELECT u.name, p.title
FROM users u
INNER JOIN posts p ON u.id = p.user_id;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="orange">LEFT JOIN</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT * FROM table1 LEFT JOIN table2 ON condition;</div>
<p class="cmd-desc">Returns all rows from left table and matching rows from right table.</p>
<div class="example-box" onclick="copyEl(this)">SELECT u.name, p.title
FROM users u
LEFT JOIN posts p ON u.id = p.user_id;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="orange">RIGHT JOIN</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT * FROM table1 RIGHT JOIN table2 ON condition;</div>
<p class="cmd-desc">Returns all rows from right table and matching rows from left table.</p>
<div class="example-box" onclick="copyEl(this)">SELECT u.name, p.title
FROM users u
RIGHT JOIN posts p ON u.id = p.user_id;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="orange">FULL OUTER JOIN</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT * FROM table1 FULL OUTER JOIN table2 ON condition;</div>
<p class="cmd-desc">Returns all rows from both tables, with NULLs for non-matching rows.</p>
<div class="example-box" onclick="copyEl(this)">SELECT u.name, p.title
FROM users u
FULL OUTER JOIN posts p ON u.id = p.user_id;</div>
<div class="click-hint">click to copy</div>
</div>
</div>
</div>
</div>
<!-- AGGREGATE FUNCTIONS -->
<div class="panel command-section" id="section-agg">
<div class="panel-header">
📊 AGGREGATE FUNCTIONS
<span class="panel-tag">AGGREGATES</span>
</div>
<div class="panel-body">
<div class="grid-2">
<div class="cmd-card">
<h3 class="cyan">COUNT</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT COUNT(*) FROM table_name;</div>
<p class="cmd-desc">Counts the number of rows or non-NULL values.</p>
<div class="example-box" onclick="copyEl(this)">-- Count all rows
SELECT COUNT(*) FROM users;
-- Count non-NULL values
SELECT COUNT(email) FROM users;
-- Count with condition
SELECT COUNT(*) FROM users WHERE age > 18;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="cyan">SUM</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT SUM(column) FROM table_name;</div>
<p class="cmd-desc">Calculates the sum of numeric values in a column.</p>
<div class="example-box" onclick="copyEl(this)">-- Sum all values
SELECT SUM(price) FROM products;
-- Sum with condition
SELECT SUM(amount) FROM orders WHERE status = 'completed';</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="cyan">AVG</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT AVG(column) FROM table_name;</div>
<p class="cmd-desc">Calculates the average of numeric values in a column.</p>
<div class="example-box" onclick="copyEl(this)">-- Average value
SELECT AVG(age) FROM users;
-- Average with rounding
SELECT ROUND(AVG(price), 2) FROM products;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="cyan">MIN / MAX</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT MIN(column), MAX(column) FROM table_name;</div>
<p class="cmd-desc">Finds the minimum and maximum values in a column.</p>
<div class="example-box" onclick="copyEl(this)">-- Min and max values
SELECT MIN(price), MAX(price) FROM products;
-- Min and max with condition
SELECT MIN(created_at), MAX(created_at) FROM users;</div>
<div class="click-hint">click to copy</div>
</div>
</div>
</div>
</div>
<!-- STRING FUNCTIONS -->
<div class="panel command-section" id="section-strings">
<div class="panel-header">
📝 STRING FUNCTIONS
<span class="panel-tag">STRINGS</span>
</div>
<div class="panel-body">
<div class="grid-2">
<div class="cmd-card">
<h3 class="pink">CONCAT</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT CONCAT(string1, string2, ...);</div>
<p class="cmd-desc">Concatenates multiple strings together.</p>
<div class="example-box" onclick="copyEl(this)">-- Concatenate strings
SELECT CONCAT(first_name, ' ', last_name) AS full_name FROM users;
-- With separator
SELECT CONCAT_WS(' - ', title, author) FROM books;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="pink">UPPER / LOWER</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT UPPER(column), LOWER(column) FROM table_name;</div>
<p class="cmd-desc">Converts strings to uppercase or lowercase.</p>
<div class="example-box" onclick="copyEl(this)">-- Convert case
SELECT UPPER(name) FROM users;
SELECT LOWER(email) FROM users;
-- Case-insensitive search
SELECT * FROM users WHERE LOWER(name) = 'john';</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="pink">SUBSTRING</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT SUBSTRING(string FROM start FOR length);</div>
<p class="cmd-desc">Extracts a substring from a string.</p>
<div class="example-box" onclick="copyEl(this)">-- Extract substring
SELECT SUBSTRING(email FROM 1 FOR 5) FROM users;
-- Extract domain
SELECT SUBSTRING(email FROM '@' FOR 50) FROM users;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="pink">LENGTH</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT LENGTH(column) FROM table_name;</div>
<p class="cmd-desc">Returns the length of a string in characters.</p>
<div class="example-box" onclick="copyEl(this)">-- String length
SELECT name, LENGTH(name) AS name_length FROM users;
-- Filter by length
SELECT * FROM users WHERE LENGTH(name) > 10;</div>
<div class="click-hint">click to copy</div>
</div>
</div>
</div>
</div>
<!-- DATE FUNCTIONS -->
<div class="panel command-section" id="section-dates">
<div class="panel-header">
📅 DATE FUNCTIONS
<span class="panel-tag">DATES</span>
</div>
<div class="panel-body">
<div class="grid-2">
<div class="cmd-card">
<h3 class="indigo">NOW()</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT NOW();</div>
<p class="cmd-desc">Returns the current date and time.</p>
<div class="example-box" onclick="copyEl(this)">-- Current timestamp
SELECT NOW();
-- Insert with current time
INSERT INTO logs (message, created_at) VALUES ('User login', NOW());</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="indigo">DATE_TRUNC</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT DATE_TRUNC('unit', timestamp);</div>
<p class="cmd-desc">Truncates a timestamp to specified precision.</p>
<div class="example-box" onclick="copyEl(this)">-- Truncate to day
SELECT DATE_TRUNC('day', created_at) FROM users;
-- Truncate to month
SELECT DATE_TRUNC('month', created_at) FROM users;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="indigo">EXTRACT</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT EXTRACT(field FROM timestamp);</div>
<p class="cmd-desc">Extracts a specific field from a timestamp.</p>
<div class="example-box" onclick="copyEl(this)">-- Extract year
SELECT EXTRACT(YEAR FROM created_at) FROM users;
-- Extract month
SELECT EXTRACT(MONTH FROM created_at) FROM users;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="indigo">AGE</h3>
<div class="syntax-box" onclick="copyEl(this)">SELECT AGE(timestamp1, timestamp2);</div>
<p class="cmd-desc">Calculates the age between two timestamps.</p>
<div class="example-box" onclick="copyEl(this)">-- Age from now
SELECT AGE(NOW(), created_at) FROM users;
-- Age between dates
SELECT AGE('2023-12-31', '2023-01-01');</div>
<div class="click-hint">click to copy</div>
</div>
</div>
</div>
</div>
<!-- INDEXES -->
<div class="panel command-section" id="section-indexes">
<div class="panel-header">
⚡ INDEXES
<span class="panel-tag">INDEXES</span>
</div>
<div class="panel-body">
<div class="grid-2">
<div class="cmd-card">
<h3 class="yellow">CREATE INDEX</h3>
<div class="syntax-box" onclick="copyEl(this)">CREATE INDEX index_name ON table_name (column);</div>
<p class="cmd-desc">Creates an index to improve query performance.</p>
<div class="example-box" onclick="copyEl(this)">-- Single column index
CREATE INDEX idx_user_email ON users (email);
-- Composite index
CREATE INDEX idx_user_name_age ON users (name, age);
-- Unique index
CREATE UNIQUE INDEX idx_user_email_unique ON users (email);</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="red">DROP INDEX</h3>
<div class="syntax-box" onclick="copyEl(this)">DROP INDEX index_name;</div>
<p class="cmd-desc">Removes an index from the database.</p>
<div class="example-box" onclick="copyEl(this)">-- Drop index
DROP INDEX idx_user_email;
-- Drop if exists
DROP INDEX IF EXISTS idx_old_index;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="yellow">List Indexes</h3>
<div class="syntax-box" onclick="copyEl(this)">\di</div>
<p class="cmd-desc">Lists all indexes in the current database.</p>
<div class="example-box" onclick="copyEl(this)">-- Alternative query
SELECT indexname, tablename FROM pg_indexes
WHERE schemaname = 'public';</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="yellow">Partial Index</h3>
<div class="syntax-box" onclick="copyEl(this)">CREATE INDEX ... WHERE condition;</div>
<p class="cmd-desc">Creates an index on a subset of rows.</p>
<div class="example-box" onclick="copyEl(this)">-- Index only active users
CREATE INDEX idx_active_users ON users (email)
WHERE status = 'active';
-- Index only recent orders
CREATE INDEX idx_recent_orders ON orders (created_at)
WHERE created_at > '2023-01-01';</div>
<div class="click-hint">click to copy</div>
</div>
</div>
</div>
</div>
<!-- VIEWS -->
<div class="panel command-section" id="section-views">
<div class="panel-header">
👁️ VIEWS
<span class="panel-tag">VIEWS</span>
</div>
<div class="panel-body">
<div class="grid-2">
<div class="cmd-card">
<h3 class="teal">CREATE VIEW</h3>
<div class="syntax-box" onclick="copyEl(this)">CREATE VIEW view_name AS SELECT ...;</div>
<p class="cmd-desc">Creates a virtual table based on a query result.</p>
<div class="example-box" onclick="copyEl(this)">-- Simple view
CREATE VIEW active_users AS
SELECT id, name, email FROM users WHERE status = 'active';
-- Complex view with joins
CREATE VIEW user_posts AS
SELECT u.name, p.title, p.created_at
FROM users u JOIN posts p ON u.id = p.user_id;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="red">DROP VIEW</h3>
<div class="syntax-box" onclick="copyEl(this)">DROP VIEW view_name;</div>
<p class="cmd-desc">Removes a view from the database.</p>
<div class="example-box" onclick="copyEl(this)">-- Drop view
DROP VIEW active_users;
-- Drop if exists
DROP VIEW IF EXISTS old_view;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="teal">List Views</h3>
<div class="syntax-box" onclick="copyEl(this)">\dv</div>
<p class="cmd-desc">Lists all views in the current database.</p>
<div class="example-box" onclick="copyEl(this)">-- Alternative query
SELECT viewname FROM pg_views
WHERE schemaname = 'public';</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="teal">Materialized View</h3>
<div class="syntax-box" onclick="copyEl(this)">CREATE MATERIALIZED VIEW ... AS SELECT ...;</div>
<p class="cmd-desc">Creates a view that stores the query result physically.</p>
<div class="example-box" onclick="copyEl(this)">-- Create materialized view
CREATE MATERIALIZED VIEW user_stats AS
SELECT COUNT(*) as total_users, AVG(age) as avg_age
FROM users;
-- Refresh materialized view
REFRESH MATERIALIZED VIEW user_stats;</div>
<div class="click-hint">click to copy</div>
</div>
</div>
</div>
</div>
<!-- TRANSACTIONS -->
<div class="panel command-section" id="section-tx">
<div class="panel-header">
🔄 TRANSACTIONS
<span class="panel-tag">TRANSACTIONS</span>
</div>
<div class="panel-body">
<div class="grid-2">
<div class="cmd-card">
<h3 class="red">BEGIN</h3>
<div class="syntax-box" onclick="copyEl(this)">BEGIN;</div>
<p class="cmd-desc">Starts a new transaction block.</p>
<div class="example-box" onclick="copyEl(this)">-- Start transaction
BEGIN;
-- Multiple operations
INSERT INTO users (name) VALUES ('John');
UPDATE users SET age = 25 WHERE name = 'John';
COMMIT;</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="green">COMMIT</h3>
<div class="syntax-box" onclick="copyEl(this)">COMMIT;</div>
<p class="cmd-desc">Commits the current transaction, making changes permanent.</p>
<div class="example-box" onclick="copyEl(this)">-- Commit transaction
BEGIN;
INSERT INTO users (name) VALUES ('Alice');
COMMIT; -- Changes are now permanent</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="red">ROLLBACK</h3>
<div class="syntax-box" onclick="copyEl(this)">ROLLBACK;</div>
<p class="cmd-desc">Rolls back the current transaction, undoing all changes.</p>
<div class="example-box" onclick="copyEl(this)">-- Rollback transaction
BEGIN;
INSERT INTO users (name) VALUES ('Bob');
ROLLBACK; -- Changes are undone</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="blue">SAVEPOINT</h3>
<div class="syntax-box" onclick="copyEl(this)">SAVEPOINT name;</div>
<p class="cmd-desc">Creates a savepoint within a transaction.</p>
<div class="example-box" onclick="copyEl(this)">-- Create savepoint
BEGIN;
INSERT INTO users (name) VALUES ('Charlie');
SAVEPOINT sp1;
INSERT INTO users (name) VALUES ('David');
ROLLBACK TO sp1; -- Rollback to savepoint</div>
<div class="click-hint">click to copy</div>
</div>
</div>
</div>
</div>
<!-- BACKUP & RESTORE -->
<div class="panel command-section" id="section-backup">
<div class="panel-header">
💾 BACKUP & RESTORE
<span class="panel-tag">BACKUP</span>
</div>
<div class="panel-body">
<div class="grid-2">
<div class="cmd-card">
<h3 class="emerald">pg_dump</h3>
<div class="syntax-box" onclick="copyEl(this)">pg_dump database_name > backup.sql</div>
<p class="cmd-desc">Creates a backup of a database to a SQL file.</p>
<div class="example-box" onclick="copyEl(this)"># Backup entire database
pg_dump myapp > backup.sql
# Backup with custom format
pg_dump -Fc myapp > backup.dump
# Backup specific schema
pg_dump -n public myapp > schema.sql</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="emerald">pg_restore</h3>
<div class="syntax-box" onclick="copyEl(this)">pg_restore -d database_name backup.dump</div>
<p class="cmd-desc">Restores a database from a backup file.</p>
<div class="example-box" onclick="copyEl(this)"># Restore from custom format
pg_restore -d myapp backup.dump
# Restore with clean
pg_restore -c -d myapp backup.dump
# Restore specific tables
pg_restore -t users -d myapp backup.dump</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="emerald">psql restore</h3>
<div class="syntax-box" onclick="copyEl(this)">psql -d database_name -f backup.sql</div>
<p class="cmd-desc">Restores a database from a SQL file.</p>
<div class="example-box" onclick="copyEl(this)"># Restore from SQL file
psql -d myapp -f backup.sql
# Restore with verbose output
psql -d myapp -f backup.sql -v ON_ERROR_STOP=1</div>
<div class="click-hint">click to copy</div>
</div>
<div class="cmd-card">
<h3 class="emerald">pg_dumpall</h3>
<div class="syntax-box" onclick="copyEl(this)">pg_dumpall > all_databases.sql</div>
<p class="cmd-desc">Backs up all databases in a PostgreSQL cluster.</p>
<div class="example-box" onclick="copyEl(this)"># Backup all databases
pg_dumpall > all_databases.sql
# Backup only globals
pg_dumpall -g > globals.sql
# Backup with roles
pg_dumpall -r > roles.sql</div>
<div class="click-hint">click to copy</div>
</div>
</div>
</div>
</div>
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