How to get the size of all tables in MSSQL

To get the size of all tables using MSSQL you can use the snippet below.

Sample MSSQL

SELECT 
    tab.NAME AS [Tablename],
    s.Name AS [Schema Name],
    part.rows AS [Count of Rows],
    SUM(a.total_pages) * 8 AS [Total Space in KB], 
    SUM(a.used_pages) * 8 AS [Used Space in KB], 
    (SUM(a.total_pages) - SUM(a.used_pages)) * 8  AS [Unused Space in KB]
FROM sys.tables tab
INNER JOIN sys.indexes idx ON tab.OBJECT_ID = idx.object_id
INNER JOIN sys.partitions part ON idx.object_id = part.OBJECT_ID AND idx.index_id = part.index_id
LEFT OUTER JOIN sys.schemas s ON tab.schema_id = s.schema_id
INNER JOIN sys.allocation_units a ON part.partition_id = a.container_id
WHERE tab.NAME NOT LIKE 'dt%' AND tab.is_ms_shipped = 0 AND idx.OBJECT_ID > 255 
GROUP BY tab.Name, s.Name, part.Rows
ORDER BY 4 DESC

How to get a list of all tables in Oracle

To get a list of all tables in Oracle you can use the following query.

SELECT owner, table_name FROM dba_tables

if your user does not have sufficient access rights to query dba_tables, you can try to query all_tables which will only show you the tables you are allowed to see.

SELECT owner, table_name FROM all_tables