Number of full table scans

Question

I would like to see information on how many times has a table been fully scanned. I was hoping for something like sys.dm_db_index_usage_stats but for table scans. There is a method described at the blog keepitsimleandfast, but I would rather get all scans since server started.

What I am looking for is also similiar to pg_stat_all_tables.seq_scan in PostgreSQL.

Answer 1

Well, that table will give you the answer you are looking for. Just join onto sys.indexes to determine the type of index. Tables are either Heaps or Clustered indexes, so a scan on that index type is a scan on the table. See the example below, add any additional columns you are looking for.

SELECT S.name AS SchemaName
    , O.name AS ObjectName
    , I.name AS IndexName
    , I.type AS IndexType
    , I.type_desc AS IndexType_Desc
    , IUS.user_scans
FROM sys.objects AS O 
    INNER JOIN sys.schemas AS S ON S.schema_id = O.schema_id
    INNER JOIN sys.indexes AS I ON I.object_id = O.object_id
    INNER JOIN sys.dm_db_index_usage_stats AS IUS ON IUS.object_id = I.object_id AND IUS.index_id = I.index_id
WHERE I.type IN (0,1) -- 0=HEAP, 1=CLUSTERED (table)