Size of all Tables in a Database

table_sizes.sql

-- PostgreSQL

SELECT
  schemaname,
  tablename,
  pg_size_pretty(size) AS size_pretty,
  pg_size_pretty(total_size) AS total_size_pretty
FROM (
  SELECT *,
    pg_relation_size(schemaname||'.'||tablename) AS size,
    pg_total_relation_size(schemaname||'.'||tablename) AS total_size
  FROM
    pg_tables
  WHERE schemaname = 'public'
  ) AS TABLES
ORDER BY total_size DESC;

-- MS SQL Server

SELECT 
    t.NAME AS TableName,
    s.Name AS SchemaName,
    p.rows AS RowCounts,
    SUM(a.total_pages) * 8 AS TotalSpaceKB, 
    SUM(a.used_pages) * 8 AS UsedSpaceKB, 
    (SUM(a.total_pages) - SUM(a.used_pages)) * 8 AS UnusedSpaceKB
FROM 
    sys.tables t
INNER JOIN      
    sys.indexes i ON t.OBJECT_ID = i.object_id
INNER JOIN 
    sys.partitions p ON i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
INNER JOIN 
    sys.allocation_units a ON p.partition_id = a.container_id
LEFT OUTER JOIN 
    sys.schemas s ON t.schema_id = s.schema_id
WHERE 
    t.NAME NOT LIKE 'dt%' 
    AND t.is_ms_shipped = 0
    AND i.OBJECT_ID > 255 
GROUP BY 
    t.Name, s.Name, p.Rows
ORDER BY 
    TotalSpaceKB DESC


-- MySQL / MariaDB

SELECT table_name AS "Tables", 
round(((data_length + index_length) / 1024 / 1024), 2) "Size in MB" 
FROM information_schema.TABLES 
WHERE table_schema = "$DB_NAME" -- <-- change this to database name
ORDER BY (data_length + index_length) DESC;