diff --git a/src/include/prefix.cpp b/src/include/prefix.cpp
index e153a158f..b7485fc5f 100755
--- a/src/include/prefix.cpp
+++ b/src/include/prefix.cpp
@@ -211,7 +211,7 @@ TToken_string & TRecord_info::relation(int logicnum)
       const int nPos = kd.FieldSeq[i] % MaxFields;          // Posizione del campo i della chiave
       const RecFieldDes& dfield = rd.Fd[nPos];              // Nome del campo i della chiave
   		int nBest = -1;
-			double dBest = ZERO;
+			double dBest = 0.0;
 
 			for (int j = 0; i < fd.NFields; j++)
 			{