chunker.rb in lhm-2.2.0

- old
+ new

@@ -23,11 +23,11 @@
     end
 
     def execute
       return unless @start && @limit
       @next_to_insert = @start
-      until @next_to_insert >= @limit
+      while @next_to_insert < @limit || (@next_to_insert == 1 && @start == 1)
         stride = @throttler.stride
         affected_rows = @connection.update(copy(bottom, top(stride)))
 
         if @throttler && affected_rows > 0
           @throttler.run
@@ -48,12 +48,12 @@
     def top(stride)
       [(@next_to_insert + stride - 1), @limit].min
     end
 
     def copy(lowest, highest)
-      "insert ignore into `#{ destination_name }` (#{ columns }) " +
-      "select #{ select_columns } from `#{ origin_name }` " +
+      "insert ignore into `#{ destination_name }` (#{ destination_columns }) " \
+      "select #{ origin_columns } from `#{ origin_name }` " \
       "#{ conditions } `#{ origin_name }`.`id` between #{ lowest } and #{ highest }"
     end
 
     def select_start
       start = connection.select_value("select min(id) from `#{ origin_name }`")
@@ -63,26 +63,26 @@
     def select_limit
       limit = connection.select_value("select max(id) from `#{ origin_name }`")
       limit ? limit.to_i : nil
     end
 
-    #XXX this is extremely brittle and doesn't work when filter contains more
-    #than one SQL clause, e.g. "where ... group by foo". Before making any
-    #more changes here, please consider either:
+    # XXX this is extremely brittle and doesn't work when filter contains more
+    # than one SQL clause, e.g. "where ... group by foo". Before making any
+    # more changes here, please consider either:
     #
-    #1. Letting users only specify part of defined clauses (i.e. don't allow
-    #`filter` on Migrator to accept both WHERE and INNER JOIN
-    #2. Changing query building so that it uses structured data rather than
-    #strings until the last possible moment.
+    # 1. Letting users only specify part of defined clauses (i.e. don't allow
+    # `filter` on Migrator to accept both WHERE and INNER JOIN
+    # 2. Changing query building so that it uses structured data rather than
+    # strings until the last possible moment.
     def conditions
       if @migration.conditions
         @migration.conditions.
-          sub(/\)\Z/, "").
-          #put any where conditions in parens
-          sub(/where\s(\w.*)\Z/, "where (\\1)") + " and"
+          sub(/\)\Z/, '').
+          # put any where conditions in parens
+          sub(/where\s(\w.*)\Z/, 'where (\\1)') + ' and'
       else
-        "where"
+        'where'
       end
     end
 
     def destination_name
       @migration.destination.name
@@ -90,20 +90,20 @@
 
     def origin_name
       @migration.origin.name
     end
 
-    def columns
-      @columns ||= @migration.intersection.joined
+    def origin_columns
+      @origin_columns ||= @migration.intersection.origin.typed(origin_name)
     end
 
-    def select_columns
-      @select_columns ||= @migration.intersection.typed("`#{origin_name}`")
+    def destination_columns
+      @destination_columns ||= @migration.intersection.destination.joined
     end
 
     def validate
       if @start && @limit && @start > @limit
-        error("impossible chunk options (limit must be greater than start)")
+        error('impossible chunk options (limit must be greater than start)')
       end
     end
   end
 end