improve parser ddl support

src/main/java/com/alibaba/druid/sql/ast/statement/SQLCreateViewStatement.java

@@ -26,6 +26,7 @@ import com.alibaba.druid.sql.visitor.SQLASTVisitor;
 public class SQLCreateViewStatement extends SQLStatementImpl implements SQLDDLStatement {
 
     private static final long     serialVersionUID = 1L;
+    private boolean               orReplace        = false;
     protected SQLName             name;
     protected SQLSelect           subQuery;
 
@@ -37,6 +38,14 @@ public class SQLCreateViewStatement extends SQLStatementImpl implements SQLDDLSt
 
     }
 
+    public boolean isOrReplace() {
+        return orReplace;
+    }
+
+    public void setOrReplace(boolean orReplace) {
+        this.orReplace = orReplace;
+    }
+
     public SQLName getName() {
         return name;
     }

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

@@ -284,11 +284,24 @@ public class MySqlStatementParser extends SQLStatementParser {
     }
 
     public SQLStatement parseCreate() {
+        char markChar = lexer.current();
+        int markBp = lexer.bp();
+
         accept(Token.CREATE);
 
+        boolean replace = false;
+        if (lexer.token() == Token.OR) {
+            lexer.nextToken();
+            acceptIdentifier("REPLACE");
+            replace = true;
+        }
+
         List<SQLCommentHint> hints = this.exprParser.parseHints();
 
         if (lexer.token() == Token.TABLE || identifierEquals(TEMPORARY)) {
+            if (replace) {
+                lexer.reset(markBp, markChar, Token.CREATE);
+            }
             MySqlCreateTableParser parser = new MySqlCreateTableParser(this.exprParser);
             MySqlCreateTableStatement stmt = parser.parseCrateTable(false);
             stmt.setHints(hints);
@@ -296,19 +309,32 @@ public class MySqlStatementParser extends SQLStatementParser {
         }
 
         if (lexer.token() == Token.DATABASE) {
+            if (replace) {
+                lexer.reset(markBp, markChar, Token.CREATE);
+            }
             return parseCreateDatabase();
         }
 
         if (lexer.token() == Token.UNIQUE || lexer.token() == Token.INDEX || identifierEquals(FULLTEXT)
             || identifierEquals(SPATIAL)) {
+            if (replace) {
+                lexer.reset(markBp, markChar, Token.CREATE);
+            }
             return parseCreateIndex();
         }
 
         if (identifierEquals(USER)) {
+            if (replace) {
+                lexer.reset(markBp, markChar, Token.CREATE);
+            }
             return parseCreateUser();
         }
-        
+
         if (lexer.token() == Token.VIEW) {
+            if (replace) {
+                lexer.reset(markBp, markChar, Token.CREATE);
+            }
+
             return parseCreateView();
         }
 
@@ -1494,7 +1520,7 @@ public class MySqlStatementParser extends SQLStatementParser {
 
         if (lexer.token() == Token.VALUES || identifierEquals("VALUE")) {
             lexer.nextToken();
-            
+
             parseValueClause(stmt.getValuesList(), 0);
         } else if (lexer.token() == Token.SELECT) {
             SQLQueryExpr queryExpr = (SQLQueryExpr) this.exprParser.expr();
@@ -1871,7 +1897,7 @@ public class MySqlStatementParser extends SQLStatementParser {
                         }
                     }
                 }
-                
+
                 SQLInsertStatement.ValuesClause values = new SQLInsertStatement.ValuesClause(valueExprList);
                 valueClauseList.add(values);
             } else {
@@ -2222,11 +2248,11 @@ public class MySqlStatementParser extends SQLStatementParser {
                     if (identifierEquals("COLUMN")) {
                         lexer.nextToken();
                     }
-                    
+
                     SQLAlterTableAlterColumn alterColumn = new SQLAlterTableAlterColumn();
                     SQLColumnDefinition columnDef = this.exprParser.parseColumn();
                     alterColumn.setColumn(columnDef);
-                    
+
                     stmt.getItems().add(alterColumn);
                 } else if (identifierEquals("CHANGE")) {
                     lexer.nextToken();

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

@@ -1078,6 +1078,7 @@ public class MySqlSchemaStatVisitor extends SchemaStatVisitor implements MySqlAS
 
     @Override
     public boolean visit(MySqlDropViewStatement x) {
+        setMode(x, Mode.Drop);
         return true;
     }
 

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/parser/SQLServerExprParser.java

@@ -129,6 +129,11 @@ public class SQLServerExprParser extends SQLExprParser {
                 accept(Token.RPAREN);
             }
             
+            if (lexer.token() == Token.PERCENT) {
+                lexer.nextToken();
+                top.setPercent(true);
+            }
+            
             return top;
         }
         

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/parser/SQLServerLexer.java

@@ -39,6 +39,7 @@ public class SQLServerLexer extends Lexer {
         map.put("TOP", Token.TOP);
         map.put("USE", Token.USE);
         map.put("WITH", Token.WITH);
+        map.put("PERCENT", Token.PERCENT);
 
         DEFAULT_SQL_SERVER_KEYWORDS = new Keywords(map);
     }

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/parser/SQLServerSelectParser.java

@@ -76,9 +76,7 @@ public class SQLServerSelectParser extends SQLSelectParser {
             }
 
             if (lexer.token() == Token.TOP) {
-                SQLServerTop top = new SQLServerTop();
-                lexer.nextToken();
-                top.setExpr(createExprParser().primary());
+                SQLServerTop top = this.createExprParser().parseTop();
                 queryBlock.setTop(top);
             }
 
@@ -101,7 +99,7 @@ public class SQLServerSelectParser extends SQLSelectParser {
         return queryRest(queryBlock);
     }
     
-    protected SQLExprParser createExprParser() {
+    protected SQLServerExprParser createExprParser() {
         return new SQLServerExprParser(lexer);
     }
 }

src/main/java/com/alibaba/druid/sql/dialect/sqlserver/visitor/SQLServerOutputVisitor.java

@@ -96,6 +96,10 @@ public class SQLServerOutputVisitor extends SQLASTOutputVisitor implements SQLSe
             print(")");
         }
         
+        if (x.isPercent()) {
+            print(" PERCENT");
+        }
+        
         return false;
     }
 

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

@@ -644,6 +644,12 @@ public class SQLStatementParser extends SQLParser {
         if (lexer.token() == Token.CREATE) {
             lexer.nextToken();
         }
+        
+        if (lexer.token() == Token.OR) {
+            lexer.nextToken();
+            acceptIdentifier("REPLACE");
+            createView.setOrReplace(true);
+        }
 
         this.accept(Token.VIEW);
 

src/main/java/com/alibaba/druid/sql/visitor/SchemaStatVisitor.java

@@ -808,6 +808,9 @@ public class SchemaStatVisitor extends SQLASTVisitorAdapter {
                 case Merge:
                     stat.incrementMergeCount();
                     break;
+                case Drop:
+                    stat.incrementDropCount();
+                    break;
                 default:
                     break;
             }