diff --git a/ast/token.go b/ast/token.go
index ed8353f421450d8ec130a3e133c9ce1206db082f..cc9306590221eda17c8d965b789a3223dc8b302d 100644
--- a/ast/token.go
+++ b/ast/token.go
@@ -45,7 +45,6 @@ const (
 var maxCachekeySize = 15
 var cacheHits int
 var cacheMisses int
-var tokenCache map[string]Token
 
 var tokenBoundaries = []string{
 	// multi character
@@ -790,7 +789,7 @@ func Tokenize(sql string) []Token {
 	var token Token
 	var tokenLength int
 	var tokens []Token
-	tokenCache = make(map[string]Token)
+	tokenCache := make(map[string]Token)
 
 	// Used to make sure the string keeps shrinking on each iteration
 	oldStringLen := len(sql) + 1