fix #535

src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlExprParser.java

@@ -253,6 +253,10 @@ public class MySqlExprParser extends SQLExprParser {
             } else if ("COLLATE".equalsIgnoreCase(lexer.stringVal())) {
                 lexer.nextToken();
 
+                if (lexer.token() == Token.EQ) {
+                    lexer.nextToken();
+                }
+                
                 if (lexer.token() != Token.IDENTIFIER) {
                     throw new ParserException("syntax error");
                 }

src/main/java/com/alibaba/druid/sql/dialect/mysql/visitor/MySqlOutputVisitor.java

@@ -389,6 +389,11 @@ public class MySqlOutputVisitor extends SQLASTOutputVisitor implements MySqlASTV
                 print(x.getCollate());
             }
         }
+        
+        if (x.getCollate() != null) {
+            print(" COLLATE ");
+            print(x.getCollate());
+        }
         return false;
     }
 

src/main/java/com/alibaba/druid/sql/parser/SQLExprParser.java

@@ -1371,7 +1371,17 @@ public class SQLExprParser extends SQLParser {
                     lexer.nextToken();
                 }
             }
+        }else if(identifierEquals("COLLATE")){
+            lexer.nextToken();
+            
+            if (lexer.token() != Token.IDENTIFIER) {
+                throw new ParserException();
+            }
+            
+            charType.setCollate(lexer.stringVal());
+            lexer.nextToken();
         }
+        
         return charType;
     }