CLX-5 Add infrastructure to unpack RBR rows recieved from CX backend.

    Add a knob to disable Select handler.

storage/clustrixdb/ha_clustrixdb.cc

@@ -5,7 +5,6 @@ Copyright (c) 2019, MariaDB Corporation.
 /** @file ha_clustrixdb.cc */
 
 #include "ha_clustrixdb.h"
-#include "ha_clustrixdb_pushdown.h"
 #include "key.h"
 
 handlerton *clustrixdb_hton = NULL;
@@ -90,10 +89,26 @@ static MYSQL_SYSVAR_STR
   NULL, NULL, ""
 );
 
+// Per thread select handler knob
+static MYSQL_THDVAR_BOOL(
+    enable_sh,
+    PLUGIN_VAR_NOCMDARG,
+    "",
+    NULL,
+    NULL,
+    1
+);
+
+bool get_enable_sh(THD* thd)
+{
+    return ( thd == NULL ) ? false : THDVAR(thd, enable_sh);
+}
+
+
+
 /****************************************************************************
 ** Class ha_clustrixdb_trx
 ****************************************************************************/
-
 st_clustrixdb_trx::st_clustrixdb_trx(THD *trx_thd)
 {
   thd = trx_thd;
@@ -178,6 +193,27 @@ void decode_objectname(char *buf, const char *path, size_t buf_size)
     buf[new_path_len] = '\0';
 }
 
+st_clustrixdb_trx *get_trx(THD *thd, int *error_code)
+{
+  *error_code = 0;
+  st_clustrixdb_trx *trx;
+  if (!(trx = (st_clustrixdb_trx *)thd_get_ha_data(thd, clustrixdb_hton)))
+  {
+    if (!(trx = new st_clustrixdb_trx(thd))) {
+      *error_code = HA_ERR_OUT_OF_MEM;
+      return NULL;
+    }
+
+    if ((*error_code = trx->net_init())) {
+      delete trx;
+      return NULL;
+    }
+
+    thd_set_ha_data(thd, clustrixdb_hton, trx);
+  }
+
+  return trx;
+}
 /****************************************************************************
 ** Class ha_clustrixdb
 ****************************************************************************/
@@ -322,6 +358,7 @@ int ha_clustrixdb::open(const char *name, int mode, uint test_if_locked)
   if (!clustrix_table_oid)
     clustrix_table_oid = atoll((const char *)table->s->tabledef_version.str);
 
+  // Surrogate key marker
   has_hidden_key = table->s->primary_key == MAX_KEY;
   if (has_hidden_key) {
     ref_length = 8;
@@ -915,28 +952,6 @@ void ha_clustrixdb::remove_current_table_from_rpl_table_list()
   delete rgi;
 }
 
-st_clustrixdb_trx *ha_clustrixdb::get_trx(THD *thd, int *error_code)
-{
-  *error_code = 0;
-  st_clustrixdb_trx *trx;
-  if (!(trx = (st_clustrixdb_trx *)thd_get_ha_data(thd, clustrixdb_hton)))
-  {
-    if (!(trx = new st_clustrixdb_trx(thd))) {
-      *error_code = HA_ERR_OUT_OF_MEM;
-      return NULL;
-    }
-
-    if ((*error_code = trx->net_init())) {
-      delete trx;
-      return NULL;
-    }
-
-    thd_set_ha_data(thd, clustrixdb_hton, trx);
-  }
-
-  return trx;
-}
-
 void ha_clustrixdb::build_key_packed_row(uint index, uchar *packed_key,
                                          size_t *packed_key_len)
 {
@@ -1088,6 +1103,7 @@ static struct st_mysql_sys_var* clustrixdb_system_variables[] =
   MYSQL_SYSVAR(password),
   MYSQL_SYSVAR(port),
   MYSQL_SYSVAR(socket),
+  MYSQL_SYSVAR(enable_sh),
   NULL
 };
 

storage/clustrixdb/ha_clustrixdb.h

@@ -21,6 +21,9 @@ Copyright (c) 2019, MariaDB Corporation.
 #include "../../sql/rpl_record.h"
 
 size_t estimate_row_size(TABLE *table);
+class st_clustrixdb_trx;
+st_clustrixdb_trx *get_trx(THD *thd, int *error_code);
+bool get_enable_sh(THD* thd);
 
 class ha_clustrixdb;
 
@@ -117,7 +120,6 @@ class ha_clustrixdb : public handler
   int info_push(uint info_type, void *info);
 
 private:
-  st_clustrixdb_trx *get_trx(THD *thd, int *error_code);
   void add_current_table_to_rpl_table_list();
   void remove_current_table_from_rpl_table_list();
   void build_key_packed_row(uint index, uchar *packed_key,

storage/clustrixdb/ha_clustrixdb_pushdown.cc

@@ -89,6 +89,10 @@ static select_handler*
 create_clustrixdb_select_handler(THD* thd, SELECT_LEX* select_lex)
 {
   ha_clustrixdb_select_handler *sh = NULL;
+  if (!get_enable_sh(thd)) {
+    return sh;
+  }
+
   String query;
   // Print the query into a string provided
   select_lex->print(thd, &query, QT_ORDINARY);
@@ -127,10 +131,10 @@ create_clustrixdb_select_handler(THD* thd, SELECT_LEX* select_lex)
 
   if ((error_code = clustrix_net->scan_query_init(query, fieldtype, items_number,
         null_bits, num_null_bytes, field_metadata, field_metadata_size, &scan_refid))) {
-    goto err;
+    //goto err;
   }
 
-  sh = new ha_clustrixdb_select_handler(thd, select_lex, clustrix_net);
+  sh = new ha_clustrixdb_select_handler(thd, select_lex, clustrix_net, scan_refid);
 
 err:
   // reuse the connection
@@ -153,10 +157,15 @@ create_clustrixdb_select_handler(THD* thd, SELECT_LEX* select_lex)
 ha_clustrixdb_select_handler::ha_clustrixdb_select_handler(
       THD *thd,
       SELECT_LEX* select_lex,
-      clustrix_connection* clustrix_net)
-  : select_handler(thd, clustrixdb_hton), clustrix_net(clustrix_net)
+      clustrix_connection* clustrix_net_,
+      ulonglong scan_refid_)
+  : select_handler(thd, clustrixdb_hton), clustrix_net(clustrix_net_),
+    scan_refid(scan_refid_)
 {
   select = select_lex;
+  rli = NULL;
+  rgi = NULL;
+  scan_refid = 0;
 }
 
 /***********************************************************
@@ -165,6 +174,9 @@ ha_clustrixdb_select_handler::ha_clustrixdb_select_handler(
  **********************************************************/
 ha_clustrixdb_select_handler::~ha_clustrixdb_select_handler()
 {
+    remove_current_table_from_rpl_table_list();
+
+    // WIP reuse the connection
     if (clustrix_net)
       delete clustrix_net;
 }
@@ -178,8 +190,16 @@ ha_clustrixdb_select_handler::~ha_clustrixdb_select_handler()
  *  rc as int
  * ********************************************************/
 int ha_clustrixdb_select_handler::init_scan()
-{
-    return 0;
+{  
+  // need this bitmap future in next_row()
+  // WIP look whether table->read_set->n_bits is valid or not
+  if (my_bitmap_init(&scan_fields, NULL, table->read_set->n_bits, false))
+    return ER_OUTOFMEMORY;
+  bitmap_set_all(&scan_fields);
+
+  add_current_table_to_rpl_table_list();
+
+  return 0;
 }
 
 /*@brief  Fetch next row for select_handler           */
@@ -193,12 +213,10 @@ int ha_clustrixdb_select_handler::init_scan()
 int ha_clustrixdb_select_handler::next_row()
 {
   int error_code = 0;
-  THD *thd = ha_thd();
   st_clustrixdb_trx *trx = get_trx(thd, &error_code);
   if (!trx)
     return error_code;
 
-  assert(is_scan);
   assert(scan_refid);
 
   uchar *rowdata;
@@ -207,12 +225,6 @@ int ha_clustrixdb_select_handler::next_row()
                                                  &rowdata_length)))
     return error_code;
 
-  if (has_hidden_key) {
-    last_hidden_key = *(ulonglong *)rowdata;
-    rowdata += 8;
-    rowdata_length -= 8;
-  }
-
   uchar const *current_row_end;
   ulong master_reclength;
 
@@ -225,24 +237,20 @@ int ha_clustrixdb_select_handler::next_row()
 
   return 0;
 
-    //return HA_ERR_END_OF_FILE;
+  //return HA_ERR_END_OF_FILE;
 }
 
 /*@brief  Finishes the scan and clean it up               */
 /***********************************************************
  * DESCRIPTION:
  * Finishes the scan for select handler
- * ATM this function sets vtable_state and restores it
- * afterwards since it reuses existed vtable code internally.
  * PARAMETERS:
  * RETURN:
  *   rc as int
  ***********************************************************/
 int ha_clustrixdb_select_handler::end_scan()
 {
-/*
   int error_code = 0;
-  THD *thd = ha_thd();
   st_clustrixdb_trx *trx = get_trx(thd, &error_code);
   if (!trx)
     return error_code;
@@ -250,13 +258,81 @@ int ha_clustrixdb_select_handler::end_scan()
   my_bitmap_free(&scan_fields);
   if (scan_refid && (error_code = trx->clustrix_net->scan_end(scan_refid)))
     return error_code;
-  scan_refid = 0;
 
-  return 0;
-*/
-    return 0;
+  return error_code;
 }
 
 void ha_clustrixdb_select_handler::print_error(int, unsigned long)
 {
 }
+
+/*@brief clone of ha_clustrixdb method                    */
+/***********************************************************
+ * DESCRIPTION:
+ * Creates structures to unpack RBR rows in ::next_row()
+ * PARAMETERS:
+ * RETURN:
+ *   rc as int
+ ***********************************************************/
+void ha_clustrixdb_select_handler::add_current_table_to_rpl_table_list()
+{
+  if (rli)
+    return;
+
+  rli = new Relay_log_info(FALSE);
+  rli->sql_driver_thd = thd;
+
+  rgi = new rpl_group_info(rli);
+  rgi->thd = thd;
+  rgi->tables_to_lock_count = 0;
+  rgi->tables_to_lock = NULL;
+  if (rgi->tables_to_lock_count)
+    return;
+
+  rgi->tables_to_lock = (RPL_TABLE_LIST *)my_malloc(sizeof(RPL_TABLE_LIST),
+                                                    MYF(MY_WME));
+  rgi->tables_to_lock->init_one_table(&table->s->db, &table->s->table_name, 0,
+                                      TL_READ);
+  rgi->tables_to_lock->table = table;
+  rgi->tables_to_lock->table_id = table->tablenr;
+  rgi->tables_to_lock->m_conv_table = NULL;
+  rgi->tables_to_lock->master_had_triggers = FALSE;
+  rgi->tables_to_lock->m_tabledef_valid = TRUE;
+  // We need one byte per column to save a column's binlog type.
+  uchar *col_type = (uchar*) my_alloca(table->s->fields);
+  for (uint i = 0 ; i < table->s->fields ; ++i)
+    col_type[i] = table->field[i]->binlog_type();
+
+  table_def *tabledef = &rgi->tables_to_lock->m_tabledef;
+  new (tabledef) table_def(col_type, table->s->fields, NULL, 0, NULL, 0);
+  rgi->tables_to_lock_count++;
+  if (col_type)
+    my_afree(col_type);
+}
+
+/*@brief clone of ha_clustrixdb method                    */
+/***********************************************************
+ * DESCRIPTION:
+ * Deletes structures that are used to unpack RBR rows 
+ * in ::next_row(). Called from dtor
+ * PARAMETERS:
+ * RETURN:
+ *   rc as int
+ ***********************************************************/
+void ha_clustrixdb_select_handler::remove_current_table_from_rpl_table_list()
+{
+  // the 2nd cond might be unnecessary
+  if (!rgi || !rgi->tables_to_lock)
+    return;
+
+  rgi->tables_to_lock->m_tabledef.table_def::~table_def();
+  rgi->tables_to_lock->m_tabledef_valid = FALSE;
+  my_free(rgi->tables_to_lock);
+  rgi->tables_to_lock_count--;
+  rgi->tables_to_lock = NULL;
+  delete rli;
+  delete rgi;
+}
+
+
+

storage/clustrixdb/ha_clustrixdb_pushdown.h

@@ -13,17 +13,13 @@ Copyright (c) 2019, MariaDB Corporation.
  *  select_handler API methods. Could be used by the server
  *  tp pushdown the whole query described by SELECT_LEX.
  *  More details in server/sql/select_handler.h
- *  sel in the constructor is the semantic tree for the query.
- *  Methods:
- *   init_scan - get plan and send it to ExeMgr. Get the execution result.
- *   next_row - get a row back from sm.
- *   end_scan - finish and clean the things up.
+ *  sel semantic tree for the query in SELECT_LEX.
  ************************************************************/
 class ha_clustrixdb_select_handler: public select_handler
 {
   public:
     ha_clustrixdb_select_handler(THD* thd_arg, SELECT_LEX* sel,
-      clustrix_connection* clustrix_net);
+      clustrix_connection* clustrix_net, ulonglong scan_refid);
     ~ha_clustrixdb_select_handler();
 
     int init_scan();
@@ -31,12 +27,15 @@ class ha_clustrixdb_select_handler: public select_handler
     int end_scan();
     void print_error(int, unsigned long);
 
+    MY_BITMAP scan_fields;
   private:
     clustrix_connection *clustrix_net;
     rpl_group_info *rgi;
+    Relay_log_info *rli;
+    RPL_TABLE_LIST *rpl_table_list;
     ulonglong scan_refid;
-    bool has_hidden_key;
-
+    void add_current_table_to_rpl_table_list();
+    void remove_current_table_from_rpl_table_list();
 };
 
 #endif