1 files changed, 71 insertions, 22 deletions

diff --git a/sql/sql_partition_admin.cc b/sql/sql_partition_admin.cc
index fee33303a04..98750314a4a 100644
--- a/sql/sql_partition_admin.cc
+++ b/sql/sql_partition_admin.cc
@@ -16,10 +16,10 @@
 #include "sql_parse.h"                      // check_one_table_access
 #include "sql_table.h"                      // mysql_alter_table, etc.
 #include "sql_lex.h"                        // Sql_statement
-#include "sql_truncate.h"                   // mysql_truncate_table,
-                                            // Truncate_statement
 #include "sql_admin.h"                      // Analyze/Check/.._table_statement
 #include "sql_partition_admin.h"            // Alter_table_*_partition
+#include "ha_partition.h"                   // ha_partition
+#include "sql_base.h"                       // open_and_lock_tables
 
 #ifndef WITH_PARTITION_STORAGE_ENGINE
 
@@ -46,7 +46,7 @@ bool Alter_table_analyze_partition_statement::execute(THD *thd)
   m_lex->alter_info.flags|= ALTER_ADMIN_PARTITION;
 
   res= Analyze_table_statement::execute(thd);
-    
+
   DBUG_RETURN(res);
 }
 
@@ -104,36 +104,85 @@ bool Alter_table_repair_partition_statement::execute(THD *thd)
 
 bool Alter_table_truncate_partition_statement::execute(THD *thd)
 {
+  int error;
+  ha_partition *partition;
+  ulong timeout= thd->variables.lock_wait_timeout;
   TABLE_LIST *first_table= thd->lex->select_lex.table_list.first;
-  bool res;
-  enum_sql_command original_sql_command;
   DBUG_ENTER("Alter_table_truncate_partition_statement::execute");
 
   /*
-    Execute TRUNCATE PARTITION just like TRUNCATE TABLE.
-    Some storage engines (InnoDB, partition) checks thd_sql_command,
-    so we set it to SQLCOM_TRUNCATE during the execution.
-  */
-  original_sql_command= m_lex->sql_command;
-  m_lex->sql_command= SQLCOM_TRUNCATE;
-  
-  /*
     Flag that it is an ALTER command which administrates partitions, used
     by ha_partition.
   */
-  m_lex->alter_info.flags|= ALTER_ADMIN_PARTITION;
-   
+  m_lex->alter_info.flags|= ALTER_ADMIN_PARTITION |
+                            ALTER_TRUNCATE_PARTITION;
+
+  /* Fix the lock types (not the same as ordinary ALTER TABLE). */
+  first_table->lock_type= TL_WRITE;
+  first_table->mdl_request.set_type(MDL_EXCLUSIVE);
+
   /*
-    Fix the lock types (not the same as ordinary ALTER TABLE).
+    Check table permissions and open it with a exclusive lock.
+    Ensure it is a partitioned table and finally, upcast the
+    handler and invoke the partition truncate method. Lastly,
+    write the statement to the binary log if necessary.
   */
-  first_table->lock_type= TL_WRITE;
-  first_table->mdl_request.set_type(MDL_SHARED_NO_READ_WRITE);
 
-  /* execute as a TRUNCATE TABLE */
-  res= Truncate_statement::execute(thd);
+  if (check_one_table_access(thd, DROP_ACL, first_table))
+    DBUG_RETURN(TRUE);
 
-  m_lex->sql_command= original_sql_command;
-  DBUG_RETURN(res);
+  if (open_and_lock_tables(thd, first_table, FALSE, 0))
+    DBUG_RETURN(TRUE);
+
+  /*
+    TODO: Add support for TRUNCATE PARTITION for NDB and other
+          engines supporting native partitioning.
+  */
+  if (first_table->table->s->db_type() != partition_hton)
+  {
+    my_error(ER_PARTITION_MGMT_ON_NONPARTITIONED, MYF(0));
+    DBUG_RETURN(TRUE);
+  }
+
+  /*
+    Under locked table modes this might still not be an exclusive
+    lock. Hence, upgrade the lock since the handler truncate method
+    mandates an exclusive metadata lock.
+  */
+  MDL_ticket *ticket= first_table->table->mdl_ticket;
+  if (thd->mdl_context.upgrade_shared_lock_to_exclusive(ticket, timeout))
+    DBUG_RETURN(TRUE);
+
+  tdc_remove_table(thd, TDC_RT_REMOVE_NOT_OWN, first_table->db,
+                   first_table->table_name, FALSE);
+
+  partition= (ha_partition *) first_table->table->file;
+
+  /* Invoke the handler method responsible for truncating the partition. */
+  if ((error= partition->truncate_partition(&thd->lex->alter_info)))
+    first_table->table->file->print_error(error, MYF(0));
+
+  /*
+    All effects of a truncate operation are committed even if the
+    operation fails. Thus, the query must be written to the binary
+    log. The only exception is a unimplemented truncate method. Also,
+    it is logged in statement format, regardless of the binlog format.
+  */
+  if (error != HA_ERR_WRONG_COMMAND)
+    error|= write_bin_log(thd, !error, thd->query(), thd->query_length());
+
+  /*
+    A locked table ticket was upgraded to a exclusive lock. After the
+    the query has been written to the binary log, downgrade the lock
+    to a shared one.
+  */
+  if (thd->locked_tables_mode)
+    ticket->downgrade_exclusive_lock(MDL_SHARED_NO_READ_WRITE);
+
+  if (! error)
+    my_ok(thd);
+
+  DBUG_RETURN(error);
 }
 
 #endif /* WITH_PARTITION_STORAGE_ENGINE */