1 files changed, 21 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3/explain_pretty_printer.rb b/activerecord/lib/active_record/connection_adapters/sqlite3/explain_pretty_printer.rb
new file mode 100644
index 0000000000..832fdfe5c4
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3/explain_pretty_printer.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module ConnectionAdapters
+    module SQLite3
+      class ExplainPrettyPrinter # :nodoc:
+        # Pretty prints the result of an EXPLAIN QUERY PLAN in a way that resembles
+        # the output of the SQLite shell:
+        #
+        #   0|0|0|SEARCH TABLE users USING INTEGER PRIMARY KEY (rowid=?) (~1 rows)
+        #   0|1|1|SCAN TABLE posts (~100000 rows)
+        #
+        def pp(result)
+          result.rows.map do |row|
+            row.join("|")
+          end.join("\n") + "\n"
+        end
+      end
+    end
+  end
+end