Added exception lauching for sqlite call that returned NULL in some cases (DB...

Added exception lauching for sqlite call that returned NULL in some cases (DB might have been corrupted).

rdbms/SqliteRset.cpp

@@ -21,6 +21,7 @@
 #include "SqliteRset.hpp"
 #include "SqliteStmt.hpp"
 #include "common/exception/Exception.hpp"
+#include "common/exception/Errnum.hpp"
 
 #include <cstring>
 #include <sstream>
@@ -218,7 +219,10 @@ optional<std::string> SqliteRset::columnOptionalString(const std::string &colNam
     if(SQLITE_NULL == idxAndType.colType) {
       return nullopt;
     } else {
-      return optional<std::string>((const char *) sqlite3_column_text(m_stmt.get(), idxAndType.colIdx));
+      const unsigned char * column_text=sqlite3_column_text(m_stmt.get(), idxAndType.colIdx);
+      cta::exception::Errnum::throwOnNull(column_text,
+        std::string("In SqliteRset::columnOptionalString(): got NULL column text for ") + colName);
+      return optional<std::string>((const char *) column_text);
     }
   } catch(exception::Exception &ex) {
     throw exception::Exception(std::string(__FUNCTION__) + " failed: " + ex.getMessage().str());