Changed DB to store node positions as Ordinals.

sql/connection.cc

Index: sql/connection.cc
diff --git a/sql/connection.cc b/sql/connection.cc
index ea3dacbb6ba025dc248590a40031cc4a508541f4..ac19d4c8fdde1518854cfc4628cbf52d37c46ca8 100644
--- a/sql/connection.cc
+++ b/sql/connection.cc
@@ -11,8 +11,8 @@
 #include "base/string_util.h"
 #include "base/stringprintf.h"
 #include "base/utf_string_conversions.h"
-#include "sql/statement.h"
 #include "third_party/sqlite/sqlite3.h"
+#include "sql/statement.h"

[rlarocque, 2012/10/01 21:45:55]

This should be in alphabetical order.

[vishwath, 2012/10/02 01:06:33]

Done.

 
 namespace {
 
@@ -455,6 +455,29 @@ bool Connection::DoesColumnExist(const char* table_name,
   return false;
 }
 
+ColType Connection::GetColumnType(char* table_name,
+                                     int column_index) const {
+  std::string sql("PRAGMA TABLE INFO(");
+  sql.append(table_name);
+  sql.append(")");
+
+  Statement statement(GetUntrackedStatement(sql.c_str()));
+  for(int i = 0; i <= column_index; i++)
+    statement.Step();
+
+  std::string column_type = statement.ColumnString(2);

[rlarocque, 2012/10/01 21:45:55]

When I suggested the PRAGMA TABLE INFO, it didn't cross my mind that this would
result in string compares here.

sqlite3_table_column_metadata() might provide an easier to use alternative.

[vishwath, 2012/10/02 01:06:33]

It turns out that the returned information is of a higher granularity than the
'fundamental' types (integer, text, blob, null). I've changed this to just
return the exact data type (bigint, varchar, etc), so that its now the callers
responsibility to make semantic sense of that return value. I see this as an
advantage, since the callers of this function can use that extra information if
necessary.

On 2012/10/01 21:45:55, rlarocque wrote:

[rlarocque, 2012/10/02 01:39:50]

Not quite what I had in mind, but that looks OK.

I'll leave it to the SQL expert to decide if this makes sense.

+  if(column_type == "INTEGER")
+    return COLUMN_TYPE_INTEGER;
+  else if(column_type == "FLOAT")
+    return COLUMN_TYPE_FLOAT;
+  else if(column_type == "TEXT")
+    return COLUMN_TYPE_TEXT;
+  else if(column_type == "BLOB")
+    return COLUMN_TYPE_BLOB;
+
+  return COLUMN_TYPE_NULL;
+}
+
 int64 Connection::GetLastInsertRowId() const {
   if (!db_) {
     DLOG(FATAL) << "Illegal use of connection without a db";