mysql parser ddl support

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

@@ -0,0 +1,38 @@
+package com.alibaba.druid.sql.ast.statement;
+
+import com.alibaba.druid.sql.ast.SQLExpr;
+import com.alibaba.druid.sql.ast.SQLStatementImpl;
+import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+
+public class SQLDropIndexStatement extends SQLStatementImpl implements SQLDDLStatement {
+
+    private static final long serialVersionUID = 1L;
+
+    private SQLExpr           indexName;
+    private SQLExpr           tableName;
+
+    public SQLExpr getIndexName() {
+        return indexName;
+    }
+
+    public void setIndexName(SQLExpr indexName) {
+        this.indexName = indexName;
+    }
+
+    public SQLExpr getTableName() {
+        return tableName;
+    }
+
+    public void setTableName(SQLExpr tableName) {
+        this.tableName = tableName;
+    }
+
+    @Override
+    protected void accept0(SQLASTVisitor visitor) {
+        if (visitor.visit(this)) {
+            acceptChild(visitor, indexName);
+            acceptChild(visitor, tableName);
+        }
+        visitor.endVisit(this);
+    }
+}