"getWhereConditions" in the postgres "QueryGenerator"

can now prepend table names to attributes. This fixes
issue #629.

lib/dialects/postgres/query-generator.js

@@ -258,7 +258,7 @@ module.exports = (function() {
       }
 
       if(options.hasOwnProperty('where')) {
-        options.where = QueryGenerator.getWhereConditions(options.where)
+        options.where = QueryGenerator.getWhereConditions(options.where, tableName)
         query += " WHERE <%= where %>"
       }
 
@@ -457,14 +457,17 @@ module.exports = (function() {
       })
     },
 
-    getWhereConditions: function(smth) {
+    getWhereConditions: function(smth, tableName) {
       var result = null
 
       if (Utils.isHash(smth)) {
+        smth = Utils.prependTableNameToHash(tableName, smth)
         result = QueryGenerator.hashToWhereConditions(smth)
       }
       else if (typeof smth === "number") {
-        result = '\"id\"' + "=" + QueryGenerator.pgEscape(smth)
+        smth = QueryGenerator.pgEscape(smth)
+        smth = Utils.prependTableNameToHash(tableName, { id: smth })
+        result = QueryGenerator.hashToWhereConditions(smth)
       }
       else if (typeof smth === "string") {
         result = smth