Further improvements of the code completion feature.

- Defined an explict DOT_SYM in the ANTLR grammar.
- Added a check in the object names cache for an existing schema when querying tables + views to avoid an exception there.
- Fixed retrieval of table spaces and logfile groups (which can return duplicates or empty values) in object name cache.
- Lowered the trigger time for code completion in an sql editor to a very small value to have it come up quicker, but it looks like something else is adding a delay there.
- Large overhaul of the auto completion code:
  + Added synonyms.
  + Optimized blocks with many single terminal alts (like the keyword and keyword_sp rules), which now use a set for quick matching.
  + Handled more ANTLR token types when parsing a grammar (e.g. label assignments).
  + Improved table reference retrieval with proper handling of nesting. Works also with invalid queries as long as the actual references are ok.
  + Added support for handling "new" and "old" column references in a create trigger statement.
  + Added support for UDFs, collations and charsets (partially, need to update the object name cache yet to deliver the actual names for them).
- Corrected the field_spec in the MySQL grammar, which was using a column reference (but needs a simple name instead).
- Corrected the engine reference in the alter_log_file_group rule, so we can show engines properly there too.

Review by: lolek (rb #11663)

backend/wbprivate/workbench/wb_context.cpp

@@ -1,5 +1,5 @@
 /* 
- * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2016, Oracle and/or its affiliates. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
@@ -2505,9 +2505,14 @@ void WBContext::request_refresh(RefreshType type, const std::string &str, Native
   refresh.str= str;
   refresh.ptr= ptr;
   refresh.timestamp= now;
+
+#if !defined(_WIN32) && !defined(__APPLE__)
+  // XXX: check this requirement. Probably already fixed since this hack was added.
+
   // Do not remove the following refresh! W/o it linux version hangs at times.
   if (refresh_gui && _pending_refreshes.empty())
     refresh_gui(RefreshNeeded, "", (NativeHandle)0);
+#endif
 
   _pending_refreshes.push_back(refresh);
 }

backend/wbpublic/sqlide/autocomplete_object_name_cache.cpp

@@ -1,5 +1,5 @@
 /* 
- * Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2016, Oracle and/or its affiliates. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
@@ -485,29 +485,35 @@ void AutoCompleteCache::refresh_tables_w(const std::string &schema)
     // TODO: check if it is possible that the connection can be locked even it was already deleted.
     base::RecMutexLock lock(_get_connection(conn));
     {
-      std::string sql = base::sqlstring("SHOW FULL TABLES FROM !", 0) << schema;
+      // Avoid an exception for an unknown schema by checking in advance.
       std::auto_ptr<sql::Statement> statement(conn->ref->createStatement());
-      std::auto_ptr<sql::ResultSet> rs(statement->executeQuery(sql));
-      if (rs.get())
+      std::string sql = base::sqlstring("show schemas like ?", 0) << schema;
+      std::auto_ptr<sql::ResultSet> rs1(statement->executeQuery(sql));
+      if (rs1.get() && rs1->next())
       {
-        while (rs->next() && !_shutdown)
+        sql = base::sqlstring("SHOW FULL TABLES FROM !", 0) << schema;
+        std::auto_ptr<sql::ResultSet> rs2(statement->executeQuery(sql));
+        if (rs2.get())
         {
-          std::string type = rs->getString(2);
-          std::string table = rs->getString(1);
-          if (type != "VIEW")
+          while (rs2->next() && !_shutdown)
           {
-            tables->push_back(table);
-
-            // Implicitly load table-local objects for each table/view.
-            add_pending_refresh(RefreshTask::RefreshColumns, schema, table);
-            add_pending_refresh(RefreshTask::RefreshTriggers, schema, table);
+            std::string type = rs2->getString(2);
+            std::string table = rs2->getString(1);
+            if (type != "VIEW")
+            {
+              tables->push_back(table);
+
+              // Implicitly load table-local objects for each table/view.
+              add_pending_refresh(RefreshTask::RefreshColumns, schema, table);
+              add_pending_refresh(RefreshTask::RefreshTriggers, schema, table);
+            }
           }
-        }
 
-        log_debug2("Found %li tables\n", (long)tables->size());
+          log_debug2("Found %li tables\n", (long)tables->size());
+        }
+        else
+          log_debug2("No tables found for %s\n", schema.c_str());
       }
-      else
-        log_debug2("No tables found for %s\n", schema.c_str());
     }
   }
 
@@ -525,28 +531,34 @@ void AutoCompleteCache::refresh_views_w(const std::string &schema)
 
     base::RecMutexLock lock(_get_connection(conn));
     {
-      std::string sql = base::sqlstring("SHOW FULL TABLES FROM !", 0) << schema;
+      // Avoid an exception for an unknown schema by checking in advance.
       std::auto_ptr<sql::Statement> statement(conn->ref->createStatement());
-      std::auto_ptr<sql::ResultSet> rs(statement->executeQuery(sql));
-      if (rs.get())
+      std::string sql = base::sqlstring("show schemas like ?", 0) << schema;
+      std::auto_ptr<sql::ResultSet> rs1(statement->executeQuery(sql));
+      if (rs1.get() && rs1->next())
       {
-        while (rs->next() && !_shutdown)
+        sql = base::sqlstring("SHOW FULL TABLES FROM !", 0) << schema;
+        std::auto_ptr<sql::ResultSet> rs2(statement->executeQuery(sql));
+        if (rs2.get())
         {
-          std::string type = rs->getString(2);
-          std::string table = rs->getString(1);
-          if (type == "VIEW")
+          while (rs2->next() && !_shutdown)
           {
-            views->push_back(table);
-
-            // Implicitly load columns for each table/view.
-            add_pending_refresh(RefreshTask::RefreshColumns, schema, table);
+            std::string type = rs2->getString(2);
+            std::string table = rs2->getString(1);
+            if (type == "VIEW")
+            {
+              views->push_back(table);
+
+              // Implicitly load columns for each table/view.
+              add_pending_refresh(RefreshTask::RefreshColumns, schema, table);
+            }
           }
-        }
 
-        log_debug2("Found %li views\n", (long)views->size());
+          log_debug2("Found %li views\n", (long)views->size());
+        }
+        else
+          log_debug2("No views found for %s\n", schema.c_str());
       }
-      else
-        log_debug2("No views found for %s\n", schema.c_str());
     }
   }
 
@@ -757,7 +769,7 @@ void AutoCompleteCache::refresh_logfile_groups_w()
       // Logfile groups and tablespaces are referenced as single unqualified identifiers in MySQL syntax.
       // They are stored however together with a table schema and a table name.
       // For auto completion however we only need to support what the syntax supports.
-      std::auto_ptr<sql::ResultSet> rs(statement->executeQuery("SELECT logfile_group_name FROM information_schema.FILES"));
+      std::auto_ptr<sql::ResultSet> rs(statement->executeQuery("SELECT distinct logfile_group_name FROM information_schema.FILES"));
       if (rs.get())
       {
         while (rs->next() && !_shutdown)
@@ -784,11 +796,15 @@ void AutoCompleteCache::refresh_tablespaces_w()
     base::RecMutexLock lock(_get_connection(conn));
     {
       std::auto_ptr<sql::Statement> statement(conn->ref->createStatement());
-      std::auto_ptr<sql::ResultSet> rs(statement->executeQuery("SELECT tablespace_name FROM information_schema.FILES"));
+      std::auto_ptr<sql::ResultSet> rs(statement->executeQuery("SELECT distinct tablespace_name FROM information_schema.FILES"));
       if (rs.get())
       {
         while (rs->next() && !_shutdown)
-          tablespaces.push_back(rs->getString(1));
+        {
+          std::string entry = rs->getString(1);
+          if (!entry.empty())
+            tablespaces.push_back(entry);
+        }
 
         log_debug2("Found %li tablespaces.\n", (long)tablespaces.size());
       }
@@ -1010,7 +1026,7 @@ void AutoCompleteCache::update_schemas(const std::vector<std::string> &schemas)
   }
   catch (std::exception &exc)
   {
-    log_error("Exception caught while updating schema name cache: %s", exc.what());
+    log_error("Exception caught while updating schema name cache: %s\n", exc.what());
   }
 }
 
@@ -1071,7 +1087,7 @@ void AutoCompleteCache::update_object_names(const std::string &cache, const std:
   }
   catch (std::exception &exc)
   {
-    log_error("Exception caught while updating object name in cache %s: %s", cache.c_str(), exc.what());
+    log_error("Exception caught while updating object name in cache %s: %s\n", cache.c_str(), exc.what());
   }
 }