Put all `explain` methods into `DatabaseStatements` module

Almost all database statements methods except `explain` was moved into
`DatabaseStatements` at #35922. This moves the last one method.

4 files changed, 14 insertions, 18 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
index d239ecff89..ef33d712ad 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -176,15 +176,6 @@ module ActiveRecord
       # DATABASE STATEMENTS ======================================
       #++
 
-      def explain(arel, binds = [])
-        sql     = "EXPLAIN #{to_sql(arel, binds)}"
-        start   = Concurrent.monotonic_time
-        result  = exec_query(sql, "EXPLAIN", binds)
-        elapsed = Concurrent.monotonic_time - start
-
-        MySQL::ExplainPrettyPrinter.new.pp(result, elapsed)
-      end
-
       # Executes the SQL statement in the context of this connection.
       def execute(sql, name = nil)
         materialize_transactions
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb b/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
index 2132e5d248..bbcdc96cdc 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
@@ -26,6 +26,15 @@ module ActiveRecord
           !READ_QUERY.match?(sql)
         end
 
+        def explain(arel, binds = [])
+          sql     = "EXPLAIN #{to_sql(arel, binds)}"
+          start   = Concurrent.monotonic_time
+          result  = exec_query(sql, "EXPLAIN", binds)
+          elapsed = Concurrent.monotonic_time - start
+
+          MySQL::ExplainPrettyPrinter.new.pp(result, elapsed)
+        end
+
         # Executes the SQL statement in the context of this connection.
         def execute(sql, name = nil)
           if preventing_writes? && write_query?(sql)
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3/database_statements.rb b/activerecord/lib/active_record/connection_adapters/sqlite3/database_statements.rb
index 73b80e8c15..85053acf91 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3/database_statements.rb
@@ -11,6 +11,11 @@ module ActiveRecord
           !READ_QUERY.match?(sql)
         end
 
+        def explain(arel, binds = [])
+          sql = "EXPLAIN QUERY PLAN #{to_sql(arel, binds)}"
+          SQLite3::ExplainPrettyPrinter.new.pp(exec_query(sql, "EXPLAIN", []))
+        end
+
         def execute(sql, name = nil) #:nodoc:
           if preventing_writes? && write_query?(sql)
             raise ActiveRecord::ReadOnlyError, "Write query attempted while in readonly mode: #{sql}"
@@ -79,7 +84,6 @@ module ActiveRecord
           log("rollback transaction", "TRANSACTION") { @connection.rollback }
         end
 
-
         private
           def execute_batch(sql, name = nil)
             if preventing_writes? && write_query?(sql)
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
index 41b35d9fc6..7f3f32162e 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -201,14 +201,6 @@ module ActiveRecord
         end
       end
 
-      #--
-      # DATABASE STATEMENTS ======================================
-      #++
-      def explain(arel, binds = [])
-        sql = "EXPLAIN QUERY PLAN #{to_sql(arel, binds)}"
-        SQLite3::ExplainPrettyPrinter.new.pp(exec_query(sql, "EXPLAIN", []))
-      end
-
       # SCHEMA STATEMENTS ========================================
 
       def primary_keys(table_name) # :nodoc: