DOCS-913: edits

Author: Sam Kleinman

source/reference/config-database.txt

@@ -37,95 +37,102 @@ Collections
    The :data:`changelog` collection stores a document for each change to
    the metadata of a sharded collection.
 
-   Each document contains the following fields:
-
-      .. data:: changeID
-
-         hostname-time-increment
-
-      .. data:: server
+   .. example::
+
+      The following example displays a single record of a chunk split
+      from a :data:`config.changelog <changelog>`` collection:
+
+      .. code-block:: javascript
+
+         {
+          "_id" : "d.local-2012-12-11T14:09:21-0",
+          "server" : "<hostanme>:<port>",
+          "clientAddr" : "127.0.0.1:63381",
+          "time" : ISODate("2012-12-11T14:09:21.039Z"),
+          "what" : "split",
+          "ns" : "<database>.<collection>",
+          "details" : {
+             "before" : {
+                "min" : {
+                   "<database>" : { $minKey : 1 }
+                },
+                "max" : {
+                   "<database>" : { $maxKey : 1 }
+                },
+                "lastmod" : Timestamp(1000, 0),
+                "lastmodEpoch" : ObjectId("000000000000000000000000")
+             },
+             "left" : {
+                "min" : {
+                   "<database>" : { $minKey : 1 }
+                },
+                "max" : {
+                   "<database>" : "<value>"
+                },
+                "lastmod" : Timestamp(1000, 1),
+                "lastmodEpoch" : ObjectId("50c73e0bca6554d8d3b19a83")
+             },
+             "right" : {
+                "min" : {
+                   "<database>" : "<value>"
+                },
+                "max" : {
+                   "<database>" : { $maxKey : 1 }
+                },
+                "lastmod" : Timestamp(1000, 2),
+                "lastmodEpoch" : ObjectId("50c73e0bca6554d8d3b19a83")
+             }
+          }
+         }
 
-         hostname
+   Each document in the :data:`changelog` collection contains the
+   following fields:
 
-      .. data:: clientAddr
+   .. What? commenting out because the description isn't clear and it
+      doesn't appear in the example above.
 
-         hostname:port of client causing change
+      .. data:: changelog.changeID
 
-      .. data:: time
+         hostname-time-increment
 
-         time change occurred
+   .. data:: changelog.server
 
-      .. data:: what
+      The hostname of the server that holds this data.
 
-         Type of change:
+      .. FACTCHECK above.
 
-            * dropCollection
-            * dropCollection.start
-            * dropDatabase
-            * dropDatabase.start
-            * moveChunk.start
-            * moveChunk.commit
-            * split
-            * multi-split
+   .. data:: changelog.clientAddr
 
-      .. data:: ns
+      A string that holds the address of the client, a
+      :program:`mongos` instance that initiates this change.
 
-         Namespace change affected.
+   .. data:: changelog.time
 
-      .. data:: details
+      A :term:`ISODate` timestamp that reflects when the change
+      occurred.
 
-         A BSON document of additional details, the contents vary
-         depending on the type of the change.
+   .. data:: changelog.what
 
+      Reflects the type of change recorded. Possible values are:
 
-.. example::
+      - ``dropCollection``
+      - ``dropCollection.start``
+      - ``dropDatabase``
+      - ``dropDatabase.start``
+      - ``moveChunk.start``
+      - ``moveChunk.commit``
+      - ``split``
+      - ``multi-split``
 
-   The following example displays a single record of a chunk split
-   from a ``config.changelog`` collection:
+   .. data:: changelog.ns
 
-   .. code-block:: javascript
+      Namespace where the change occured.
 
-      {
-      "_id" : "d.local-2012-12-11T14:09:21-0",
-      "server" : "d.local",
-      "clientAddr" : "127.0.0.1:63381",
-      "time" : ISODate("2012-12-11T14:09:21.039Z"),
-      "what" : "split",
-      "ns" : "snps.elegans",
-      "details" : {
-         "before" : {
-            "min" : {
-               "snp" : { $minKey : 1 }
-            },
-            "max" : {
-               "snp" : { $maxKey : 1 }
-            },
-            "lastmod" : Timestamp(1000, 0),
-            "lastmodEpoch" : ObjectId("000000000000000000000000")
-         },
-         "left" : {
-            "min" : {
-               "snp" : { $minKey : 1 }
-            },
-            "max" : {
-               "snp" : "haw54524"
-            },
-            "lastmod" : Timestamp(1000, 1),
-            "lastmodEpoch" : ObjectId("50c73e0bca6554d8d3b19a83")
-         },
-         "right" : {
-            "min" : {
-               "snp" : "haw54524"
-            },
-            "max" : {
-               "snp" : { $maxKey : 1 }
-            },
-            "lastmod" : Timestamp(1000, 2),
-            "lastmodEpoch" : ObjectId("50c73e0bca6554d8d3b19a83")
-            }
-         }
-      }
+   .. data:: changelog.details
 
+      A :term:`document` that contains  additional details regarding
+      the change. The structure of the :data:`~changelog.details`
+      document depends on the type of change.
 
 .. data:: chunks