This query yields identical numbers to the existing query, but returns in less than a second instead of 30+ seconds

Author: neilschelly

default-metrics.toml

@@ -47,74 +47,67 @@ context = "tablespace"
 labels = [ "tablespace", "type" ]
 metricsdesc = { bytes = "Generic counter metric of tablespaces bytes in Oracle.", max_bytes = "Generic counter metric of tablespaces max bytes in Oracle.", free = "Generic counter metric of tablespaces free bytes in Oracle." }
 request = '''
-  SELECT
-    Z.name       as tablespace,
-    dt.contents  as type,
-    Z.bytes      as bytes,
-    Z.max_bytes  as max_bytes,
-    Z.free_bytes as free
-  FROM
+SELECT
+  df.tablespace_name       as tablespace,
+  df.type                  as type,
+  sum(df.bytes)            as bytes,
+  sum(df.max_bytes)        as max_bytes,
+  sum(f.free)              as free
+FROM
   (
     SELECT
-      X.name                   as name,
-      SUM(nvl(X.free_bytes,0)) as free_bytes,
-      SUM(X.bytes)             as bytes,
-      SUM(X.max_bytes)         as max_bytes
+      ddf.file_id,
+      dt.contents as type,
+      ddf.file_name,
+      ddf.tablespace_name,
+      TRUNC(ddf.bytes) as bytes,
+      TRUNC(GREATEST(ddf.bytes,ddf.maxbytes)) as max_bytes
     FROM
-      (
-        SELECT
-          ddf.tablespace_name as name,
-          ddf.status as status,
-          ddf.bytes as bytes,
-          sum(coalesce(dfs.bytes, 0)) as free_bytes,
-          CASE
-            WHEN ddf.maxbytes = 0 THEN ddf.bytes
-            ELSE ddf.maxbytes
-          END as max_bytes
-        FROM
-          sys.dba_data_files ddf,
-          sys.dba_tablespaces dt,
-          sys.dba_free_space dfs
-        WHERE ddf.tablespace_name = dt.tablespace_name
-        AND ddf.file_id = dfs.file_id(+)
-        GROUP BY
-          ddf.tablespace_name,
-          ddf.file_name,
-          ddf.status,
-          ddf.bytes,
-          ddf.maxbytes
-      ) X
-    GROUP BY X.name
-    UNION ALL
+      dba_data_files ddf,
+      dba_tablespaces dt
+    WHERE ddf.tablespace_name = dt.tablespace_name
+  ) df,
+  (
     SELECT
-      Y.name                   as name,
-      MAX(nvl(Y.free_bytes,0)) as free_bytes,
-      SUM(Y.bytes)             as bytes,
-      SUM(Y.max_bytes)         as max_bytes
-    FROM
+      TRUNC(SUM(bytes)) AS free,
+      file_id
+    FROM dba_free_space
+    GROUP BY file_id
+  ) f
+WHERE df.file_id = f.file_id (+)
+GROUP BY df.tablespace_name, df.type
+UNION ALL
+SELECT
+  Y.name                   as tablespace_name,
+  Y.type                   as type,
+  SUM(Y.bytes)             as bytes,
+  SUM(Y.max_bytes)         as max_bytes,
+  MAX(nvl(Y.free_bytes,0)) as free
+FROM
+  (
+    SELECT
+      dtf.tablespace_name as name,
+      dt.contents as type,
+      dtf.status as status,
+      dtf.bytes as bytes,
       (
         SELECT
-          dtf.tablespace_name as name,
-          dtf.status as status,
-          dtf.bytes as bytes,
-          (
-            SELECT
-              ((f.total_blocks - s.tot_used_blocks)*vp.value)
-            FROM
-              (SELECT tablespace_name, sum(used_blocks) tot_used_blocks FROM gv$sort_segment WHERE  tablespace_name!='DUMMY' GROUP BY tablespace_name) s,
-              (SELECT tablespace_name, sum(blocks) total_blocks FROM dba_temp_files where tablespace_name !='DUMMY' GROUP BY tablespace_name) f,
-              (SELECT value FROM v$parameter WHERE name = 'db_block_size') vp
-            WHERE f.tablespace_name=s.tablespace_name AND f.tablespace_name = dtf.tablespace_name
-          ) as free_bytes,
-          CASE
-            WHEN dtf.maxbytes = 0 THEN dtf.bytes
-            ELSE dtf.maxbytes
-          END as max_bytes
+          ((f.total_blocks - s.tot_used_blocks)*vp.value)
         FROM
-          sys.dba_temp_files dtf
-      ) Y
-    GROUP BY Y.name
-  ) Z, sys.dba_tablespaces dt
-  WHERE
-    Z.name = dt.tablespace_name
+          (SELECT tablespace_name, sum(used_blocks) tot_used_blocks FROM gv$sort_segment WHERE  tablespace_name!='DUMMY' GROUP BY tablespace_name) s,
+          (SELECT tablespace_name, sum(blocks) total_blocks FROM dba_temp_files where tablespace_name !='DUMMY' GROUP BY tablespace_name) f,
+          (SELECT value FROM v$parameter WHERE name = 'db_block_size') vp
+        WHERE f.tablespace_name=s.tablespace_name AND f.tablespace_name = dtf.tablespace_name
+      ) as free_bytes,
+      CASE
+        WHEN dtf.maxbytes = 0 THEN dtf.bytes
+        ELSE dtf.maxbytes
+      END as max_bytes
+    FROM
+      sys.dba_temp_files dtf,
+      sys.dba_tablespaces dt
+    WHERE dtf.tablespace_name = dt.tablespace_name
+  ) Y
+GROUP BY Y.name, Y.type
+ORDER BY tablespace
 '''