partial implementation

query_classifier/query_classifier.cc

@@ -736,15 +736,17 @@ static skygw_query_type_t resolve_query_type(
                         }
                 } /**< for */
 #if defined(TEMPORARY_TABLES)                
-                if ((skygw_query_type_t)type == QUERY_TYPE_READ)
+		if ((skygw_query_type_t)type == QUERY_TYPE_READ)
-                {
+		  {
-                        /** 
+		    /** 
-			 * Find out the database name and all tables the query 
+		     * Find out the database name and all tables the query 
-			 * uses. Create a hashvalue from each and if any of the 
+		     * uses. Create a hashvalue from each and if any of the 
-			 * values can be found from property's hashtable, set 
+		     * values can be found from property's hashtable, set 
-			 * query type to QUERY_TYPE_READ_TMP_TABLE.
+		     * query type to QUERY_TYPE_READ_TMP_TABLE.
-                         */
+		     */
-                }
+
+		  
+		  }
 #endif
         } /**< if */
 return_qtype:
@@ -874,8 +876,8 @@ char* skygw_query_classifier_get_stmtname(
 /**
 
  * Finds the head of the list of tables affected by the current select statement.
- * @param thd Pointer to a valid thread descriptor structure
+ * @param thd Pointer to a valid THD
- * @return Head of the TABLE_LIST chain or NULL in case of an error
+ * @return Pointer to the head of the TABLE_LIST chain or NULL in case of an error
  */
 void* skygw_get_affected_tables(void* thdp)
 {
@@ -893,6 +895,92 @@ void* skygw_get_affected_tables(void* thdp)
 
         return (void*)thd->lex->current_select->table_list.first;
 }
+
+
+/**
+ * Reads the parsetree and lists all the affected tables and views in the query.
+ * In the case of an error, the size of the table is set to zero and no memory is allocated.
+ * The caller must free the allocated memory.
+ *
+ * @param querybuf GWBUF where the table names are extracted from
+ * @param tblsize Pointer where the number of tables is written
+ * @return Array of null-terminated strings with the table names
+ */
+char** skygw_get_table_names(GWBUF* querybuf,int* tblsize)
+{
+  parsing_info_t* pi;
+  MYSQL*          mysql;
+  THD*            thd;
+  TABLE_LIST*     tbl;
+  SELECT_LEX*slx;
+  int i = 0, currtblsz = 0;
+  char**tables,**tmp;
+        
+  if (!GWBUF_IS_PARSED(querybuf))
+    {
+      tables = NULL;
+      goto retblock;
+    }
+  pi = (parsing_info_t *)gwbuf_get_buffer_object_data(querybuf, 
+						      GWBUF_PARSING_INFO);
+
+  if (pi == NULL)
+    {
+      tables = NULL;
+      goto retblock;                
+    }
+        
+  if (pi->pi_query_plain_str == NULL || 
+      (mysql = (MYSQL *)pi->pi_handle) == NULL || 
+      (thd = (THD *)mysql->thd) == NULL)
+    {
+      ss_dassert(pi->pi_query_plain_str != NULL &&
+		        mysql != NULL && 
+		 thd != NULL);
+      tables = NULL;
+      goto retblock;
+    }
+
+  thd->lex->current_select = thd->lex->all_selects_list;    
+
+  while(thd->lex->current_select){
+    
+    tbl = (TABLE_LIST*)skygw_get_affected_tables(thd);
+
+    while (tbl) 
+      {
+	if(i >= currtblsz){
+	  
+	  tmp = (char**)malloc(sizeof(char*)*(currtblsz*2+1));
+
+	  if(tmp){
+	    if(currtblsz > 0){
+	      int x;
+	      for(x = 0;x<currtblsz;x++){
+		tmp[x] = tables[x]; 
+	      }
+	      free(tables);
+	    }
+
+	    tables = tmp;
+	    currtblsz = currtblsz*2 + 1;
+
+	  }
+	  
+	  
+	}
+	tables[i++] = strdup(tbl->alias);
+	tbl=tbl->next_local;
+      }
+    thd->lex->current_select = thd->lex->current_select->next_select_in_list();
+  }
+
+ retblock:
+  *tblsize = i;
+  return tables;
+}
+
+
 /*
  * Replace user-provided literals with question marks. Return a copy of the
  * querystr with replacements.

query_classifier/query_classifier.h

@@ -73,6 +73,8 @@ skygw_query_type_t query_classifier_get_type(GWBUF* querybuf);
 
 /** Free THD context and close MYSQL */
 char*           skygw_query_classifier_get_stmtname(MYSQL* mysql);
+void*		skygw_get_affected_tables(void* thdp);
+char**		skygw_get_table_names(GWBUF* querybuf,int* tblsize);
 char*           skygw_get_canonical(GWBUF* querybuf);
 bool            parse_query (GWBUF* querybuf);
 parsing_info_t* parsing_info_init(void (*donefun)(void *));

server/modules/include/readwritesplit.h

@@ -145,7 +145,7 @@ struct rses_property_st {
         union rses_prop_data {
                 mysql_sescmd_t  sescmd;
                 HASHTABLE       tmp_table_hash;
-		void*           placeholder; /*< to be removed due new type */
+		HASHTABLE*	temp_tables;
         } rses_prop_data;
         rses_property_t*     rses_prop_next; /*< next property of same type */
 #if defined(SS_DEBUG)

server/modules/routing/readwritesplit/readwritesplit.c

@@ -273,6 +273,33 @@ static bool have_enough_servers(
 static SPINLOCK	        instlock;
 static ROUTER_INSTANCE* instances;
 
+static int hashkeyfun(void* key);
+static int hashcmpfun (void *, void *);
+
+static int hashkeyfun(
+		void* key)
+{
+  unsigned int hash = 0,c = 0;
+  char* ptr = (char*)key;
+  while((c = *ptr++)){
+    hash = c + (hash << 6) + (hash << 16) - hash;
+  }
+  return *(int *)key;
+}
+
+static int hashcmpfun(
+		  void* v1,
+		  void* v2)
+{
+  int i1;
+  int i2;
+
+  i1 = *(int *)v1;
+  i2 = *(int *)v2;
+
+  return (i1 < i2 ? -1 : (i1 > i2 ? 1 : 0));
+}
+
 /**
  * Implementation of the mandatory version entry point
  *
@@ -1034,12 +1061,21 @@ static int routeQuery(
         skygw_query_type_t qtype          = QUERY_TYPE_UNKNOWN;
         mysql_server_cmd_t packet_type;
         uint8_t*           packet;
-        int                ret = 0;
+        int                ret = 0,
+			   tsize = 0,
+			   klen = 0,
+			   i = 0;
         DCB*               master_dcb     = NULL;
         DCB*               slave_dcb      = NULL;
         ROUTER_INSTANCE*   inst = (ROUTER_INSTANCE *)instance;
         ROUTER_CLIENT_SES* router_cli_ses = (ROUTER_CLIENT_SES *)router_session;
+	rses_property_t*   rses_prop;
         bool               rses_is_closed = false;
+	bool		   target_tmp_table = false;
+	char		   *dbname,*hkey;
+	char**		   tbl;
+	HASHTABLE*	   h;
+	MYSQL_session*     data;
 
         CHK_CLIENT_RSES(router_cli_ses);
 
@@ -1053,6 +1089,7 @@ static int routeQuery(
         
         packet = GWBUF_DATA(querybuf);
         packet_type = packet[4];
+	rses_prop = *router_cli_ses->rses_properties;
         
         if (rses_is_closed)
         {
@@ -1083,6 +1120,9 @@ static int routeQuery(
 
         master_dcb = router_cli_ses->rses_master_ref->bref_dcb;
         CHK_DCB(master_dcb);
+	
+	data = (MYSQL_session*)master_dcb->session->data;
+	dbname = data->db;
         
         switch(packet_type) {
                 case MYSQL_COM_QUIT:        /*< 1 QUIT will close all sessions */
@@ -1128,6 +1168,51 @@ static int routeQuery(
                         break;
         } /**< switch by packet type */
 
+
+	/**
+	 *Check if the query targets a temporary table
+	 */
+	if(QUERY_IS_TYPE(qtype, QUERY_TYPE_READ)){
+	  
+
+	  tbl = skygw_get_table_names(querybuf,&tsize);
+
+	  if(tsize > 0)
+	    { /**Query targets at least one table*/
+	      for(i = 0;i<tsize && !target_tmp_table && tbl[i];i++){
+		klen = strlen(dbname) + strlen(tbl[i]) + 2;
+		hkey = calloc(klen,sizeof(char));
+		strcpy(hkey,dbname);
+		strcat(hkey,".");
+		strcat(hkey,tbl[0]);
+		if(rses_prop && rses_prop->rses_prop_data.temp_tables){
+		  if((target_tmp_table = hashtable_fetch(rses_prop->rses_prop_data.temp_tables,(void *)hkey)))
+		    {
+		      /**Query target is a temporary table*/
+			
+		      LOGIF(LT, (skygw_log_write(
+						 LOGFILE_TRACE,
+						 "Query targets a temporary table: %s",hkey)));
+		    }
+		}
+
+
+
+	      }
+
+	      for(i = 0;i<tsize;i++){
+		free(tbl[i]);
+	      }
+	      free(tbl); 
+
+	    }
+
+
+
+
+
+	}
+
         /**
          * If autocommit is disabled or transaction is explicitly started
          * transaction becomes active and master gets all statements until
@@ -1189,7 +1274,8 @@ static int routeQuery(
                 goto return_ret;
         }
         else if (QUERY_IS_TYPE(qtype, QUERY_TYPE_READ) && 
-                !router_cli_ses->rses_transaction_active)
+                !router_cli_ses->rses_transaction_active && 
+		 !target_tmp_table)
         {
                 bool succp;
                 
@@ -1263,19 +1349,98 @@ static int routeQuery(
                 {
                         goto return_ret;
                 }           
-#if defined(TEMPORARY_TABLES)
+
+		//#if defined(TEMPORARY_TABLES)
+		
+		if(!query_is_parsed(querybuf) && !parse_query(querybuf)){
+		 			LOGIF(LE, (skygw_log_write(
+						   LOGFILE_ERROR,
+						   "Error: Unable to parse query.")));
+		}
+		qtype = query_classifier_get_type(querybuf);
+
+		if(QUERY_IS_TYPE(qtype, QUERY_TYPE_CREATE_TMP_TABLE)){
+		 
+		  
+		  
+		  bool is_temp = true;
+		 		  
+
+		  if(rses_prop == NULL){
+		    if((rses_prop = 
+			(rses_property_t*)calloc(1,sizeof(rses_property_t)))){
+		      rses_prop->rses_prop_rsession = router_cli_ses;
+		      rses_prop->rses_prop_refcount = 1;
+		      rses_prop->rses_prop_next = NULL;
+		      rses_prop->rses_prop_type = RSES_PROP_TYPE_SESCMD;
+		      *router_cli_ses->rses_properties = rses_prop;
+		    }
+		    
+		  }
+		    
+		  if( rses_prop->rses_prop_data.temp_tables == NULL){
+		    
+		    h = hashtable_alloc(10000, hashkeyfun, hashcmpfun);
+
+		    if(h){
+		      rses_prop->rses_prop_data.temp_tables = h;
+		    }
+
+		  }
+
+		  tbl = skygw_get_table_names(querybuf,&tsize);
+
+		  if(tsize == 1 && tbl[0])
+		    { /**One valid table created*/
+
+		  klen = strlen(dbname) + strlen(tbl[0]) + 2;
+		  hkey = calloc(klen,sizeof(char));
+		  strcpy(hkey,dbname);
+		  strcat(hkey,".");
+		  strcat(hkey,tbl[0]);
+
+		    if(
+		       hashtable_add(
+				  rses_prop->rses_prop_data.temp_tables,
+				  (void *)hkey,
+				  (void *)&is_temp
+				     )
+		       == 0) /**Conflict in hash table*/
+		      {
+			LOGIF(LT, (skygw_log_write(
+						   LOGFILE_TRACE,
+						   "Temporary table conflict in hashtable: %s",hkey)));
+		      }
+		    char* retkey = hashtable_fetch(
+						   rses_prop->rses_prop_data.temp_tables,
+						   hkey);
+		    if(retkey){
+LOGIF(LT, (skygw_log_write(
+						   LOGFILE_TRACE,
+						   "Temporary table added: %s",retkey)));
+		    }
+		    }
+
+		  if(tsize > 0){
+		    for(i = 0;i<tsize;i++){
+		      free(tbl[i]);
+		    }
+		    free(tbl);
+		  }
+		}
 		/** 
 		 * If query is of type QUERY_TYPE_CREATE_TMP_TABLE then find out 
 		 * the database and table name, create a hashvalue and 
 		 * add it to the router client session's property. If property 
 		 * doesn't exist then create it first. 
 		 */
-#endif
+
+		//#endif
                 
                 if (master_dcb == NULL)
-                {
+		  {
-                        succp = get_dcb(&master_dcb, router_cli_ses, BE_MASTER);
+		    succp = get_dcb(&master_dcb, router_cli_ses, BE_MASTER);
-                }
+		  }
                 
                 if (succp)
                 {
@@ -2671,11 +2836,24 @@ static bool execute_sescmd_in_backend(
                         break;
 
 		case MYSQL_COM_INIT_DB:
-#if defined(TEMPORARY_TABLES)			
+		  //#if defined(TEMPORARY_TABLES)			
-			/**
+	  /**
-			 * Record database name and store to session.
+	   * Record database name and store to session.
-			 */
+	   */
-#endif
+
+	  {
+
+	    GWBUF* tmpbuf;
+	    MYSQL_session* data;
+	    unsigned int qlen;
+
+	    data = dcb->session->data;
+	    tmpbuf = scur->scmd_cur_cmd->my_sescmd_buf;
+	    qlen = MYSQL_GET_PACKET_LEN((unsigned char*)tmpbuf->start);
+	    strncpy(data->db,tmpbuf->start+5,qlen - 1);
+		    
+	  }
+	  //#endif
 		case MYSQL_COM_QUERY:
                 default:
                         /**