[sql] Database recovery system for Shortcuts.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 4efad5d71eff4c442afd7346449956087716a504..57a1b7673077bbebfe3c8e7242162f0acfe95c6a 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -54083,6 +54083,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
     Records specific failure and success cases in sql::Recovery implementation,
     to determine which cases (if any) might be worth writing additional
     automated recovery code for, versus which should lead to clearing databases.
+    RECOVERY_FAILED_AUTORECOVERDB_SCHEMACREATE and
+    RECOVERY_FAILED_AUTORECOVERDB_SCHEMASELECT are subsets of
+    RECOVERY_FAILED_AUTORECOVERDB_SCHEMA.

[Mark P, 2016/06/27 23:20:13]

Kind of done.  These are subsets, true.  But I _think_ there are other subsets
here too.
Please either
- be complete and list all subsets.
- be vague and simply state that there are certain types of errors that cause an
emission to multiple buckets.  (Read code for details.)
The current phrasing implies this list is complete (which I'm skeptical of given
your other comments).

[Scott Hess - ex-Googler, 2016/06/29 21:39:30]

Reworded the description to emphasis that this is to inform the development
cycle, not indicate that anything actionable is going wrong.  And point at
recovery.cc.

   </summary>
 </histogram>
 
@@ -89761,6 +89764,33 @@ To add a new entry, add it with any value and run test to compute valid value.
   <int value="19" label="RECOVERY_FAILED_META_NO_VERSION">
     GetMetaVersionNumber() found no version row in meta table.
   </int>
+  <int value="20" label="RECOVERY_SUCCESS_AUTORECOVERDB">
+    sql::Recovery::RecoverDatabaseOrRaze() completed successfully.
+  </int>
+  <int value="21" label="RECOVERY_FAILED_AUTORECOVERDB_BEGIN">
+    Autorecover could not setup the database for recovery.
+  </int>
+  <int value="22" label="RECOVERY_FAILED_AUTORECOVERDB_SCHEMA">
+    Autorecover could not copy existing schema.
+  </int>
+  <int value="23" label="RECOVERY_FAILED_AUTORECOVERDB_SCHEMACREATE">
+    Autorecover could not create new db schema, subset of _SCHEMA.
+  </int>
+  <int value="24" label="RECOVERY_FAILED_AUTORECOVERDB_SCHEMASELECT">
+    Autorecover could not read corrupt db schema, subset of _SCHEMA.
+  </int>
+  <int value="25" label="RECOVERY_FAILED_AUTORECOVERDB_NAMESELECT">
+    Autorecover could not read table names to copy.
+  </int>
+  <int value="26" label="RECOVERY_FAILED_AUTORECOVERDB_TABLE">
+    Autorecover failed recovering a table.
+  </int>
+  <int value="27" label="RECOVERY_FAILED_AUTORECOVERDB_SEQUENCE">
+    Autorecover failed recovering sequence table.
+  </int>
+  <int value="28" label="RECOVERY_FAILED_AUTORECOVERDB_AUX">
+    Autorecover failed recovering triggers, views, or virtual tables.
+  </int>
 </enum>
 
 <enum name="SqliteStatsEnum" type="int">