In this post, I am sharing a script for finding the largest object of a SQL Server Database.
Whenever I find any handy script which we can use in day to day work, I am sharing without fail.

When you are doing the database clean up or maintenance activity, you probably need to check the big size of objects.

I already shared few couples of the script on checking the size of table, database, log files.

SQL Server: Find the total row count and size of the Tables

SQL Server: Script to check the size of Query Plan Cache

SQL Server: Script to find the size of Database Files and Log Files

Here, below script is used for finding the largest object of a database:

SELECT 
    t.NAME AS TableName
    ,i.name as indexName
    ,sum(p.rows) as RowCounts
    ,sum(a.total_pages) as TotalPages
    ,sum(a.used_pages) as UsedPages
    ,sum(a.data_pages) as DataPages
    ,(sum(a.total_pages) * 8) / 1024 as TotalSpaceMB
    ,(sum(a.used_pages) * 8) / 1024 as UsedSpaceMB 
    ,(sum(a.data_pages) * 8) / 1024 as DataSpaceMB
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
WHERE t.NAME NOT LIKE 'dt%' 
	AND i.OBJECT_ID > 255 
	AND i.index_id <= 1
GROUP BY 
    t.NAME, i.object_id, i.index_id, i.name 
ORDER BY SUM(a.total_pages) DESC

In this post, I am sharing few important function for finding the size of database, table and index in PostgreSQL.

Script 1 : Find a total size of the database.

SELECT pg_size_pretty(pg_database_size('db_employee'));

Script 2: Find a total size of the table with an index.

SELECT pg_size_pretty(pg_total_relation_size('Employee_Table'));

Script 3: Find a total size of the table without an index.

SELECT pg_size_pretty(pg_relation_size('Employee_table'));

Script 4: Find a total size of the index.

SELECT pg_size_pretty(pg_indexes_size('index_empid'));

Script 5: Find a total number of rows in a table.

SELECT COUNT(1) FROM Employee_table;

Script 6 : Find all the table size in the current database.

SELECT
    table_schema || '.' || table_name AS TableName,
    pg_size_pretty(pg_total_relation_size('"' || table_schema || '"."' || table_name || '"')) AS TableSize
FROM information_schema.tables
ORDER BY
    pg_total_relation_size('"' || table_schema || '"."' || table_name || '"') DESC

Script 7 : Find all the table and index size in the current database.

SELECT
    TableName
    ,pg_size_pretty(pg_table_size(TableName)) AS TableSize
    ,pg_size_pretty(pg_indexes_size(TableName)) AS IndexSize
    ,pg_size_pretty(pg_total_relation_size(TableName)) AS TotalSize
FROM 
(
     SELECT ('"' || table_schema || '"."' || table_name || '"') AS TableName
     FROM information_schema.tables
) AS Tables
ORDER BY 4 DESC