[postgis-users] PostgreSQL 7.3 Support

[carl anderson]

On 2002.12.06 11:37 Paul Ramsey wrote:
> Does mapserver not work for you now? Our hope was that only PostGIS 
> would need to be changed to support PgSQL 7.3, not the mapserver 
> connector. How is mapserver failing against 7.3?
> 

Well....

EXPLAIN <plan> now returns a tupleset to return results instead of 
using the NOTICES facility to push a single multiline message.  So 
mapserver has no idea about field types.

I am very much in favor of the new EXPLAIN <plan>, as it allows plan 
results to be saved/printed much easier.

attached is a patch against mapserver 3.6.3

C.

ps
    I submitted this to [postgis-users] a couple of weeks ago but 
forgot not to use multipart-mime.  There are other patches, mostly 
doing what is already in CVS if you want them.


----------------------------------
Carl Anderson
candrsn at mindspring.com

New Hampshire tells us "common sense for all"
     where can I get mine?
----------------------------------


-------------------------------------------------------------------
diff -ur mapserver-3.6.3.old/mappostgis.c mapserver-3.6.3/mappostgis.c
--- mapserver-3.6.3.old/mappostgis.c	Tue Jun 25 20:52:38 2002
+++ mapserver-3.6.3/mappostgis.c	Fri Nov 22 16:41:30 2002
@@ -35,8 +35,9 @@
  {
  	char	*str,*str2;
  	char  *result;
-	 
-	if (strstr(message,"QUERY DUMP"))
+
+fprintf(stderr,"NH %s \n",message);
+	if (strstr(message,"QUERY DUMP:"))
  	{
  		if (	((msPOSTGISLayerInfo *) arg)->fields)
  		{
@@ -1141,13 +1142,15 @@
   	msPOSTGISLayerParseData(layer->data, geom_column_name, 
table_name, urid_name, user_srid);
  +       query_result = PQexec(layerinfo->conn, "set 
explain_pretty_print = on");
+// in pre 7.3 databases this will fail so relax
+
  	// two cases here.  One, its a table (use select * from table) 
otherwise, just use the select clause
  	sprintf(sql,"EXPLAIN VERBOSE SELECT * FROM %s",table_name);
  		// this will call the postresql_NOTICE_HANDLER() 
callback!  layer->fields will be populated
  	query_result = PQexec(layerinfo->conn, sql );
  -
-    if (!(query_result) || PQresultStatus(query_result) != 
PGRES_COMMAND_OK)
+    if (!(query_result) || (PQresultStatus(query_result) != 
PGRES_COMMAND_OK && PQresultStatus(query_result) != PGRES_TUPLES_OK ))
      {
  		char tmp[4000];
  @@ -1159,6 +1162,44 @@
  	  	query_result = NULL;
  		return(MS_FAILURE);
      }
+
+   if (PQresultStatus(query_result) == PGRES_TUPLES_OK )
+   {
+     //build layerinfo->fields from tuples passed back
+     int	rows,row;
+     char	*result;
+     char	*tup;
+     char	*str,*str2;
+
+     if (  layerinfo->fields )
+     {
+       free(layerinfo->fields);     // free up space
+     }
+     result = malloc ( 6000) ;
+     layerinfo->fields = result;
+     result[0] = 0; //null terminate it
+
+     rows = PQntuples(query_result);
+     for ( row=0; row < rows; row++ )
+     {
+       tup = PQgetvalue(query_result,row,0);
+       str = strstr(tup,":resname ");
+       if ( str )
+       {
+         str += 9;
+         str2 = strstr(str," ");
+         if  (strncmp(str, "<>", (str2-str)))
+         {
+           if ( strlen(result) > 0 )
+           {
+             strcat(result,",");
+	   }
+		strncat(result,str,(str2-str));
+ 	 }
+       }
+     }
+    }
+
  	//layerinfo->fields is a string with a list of all the columns