From ed15dd4d78bb127bf17f38aa9a0e8e1381504726 Mon Sep 17 00:00:00 2001
From: wenshao <szujobs@hotmail.com>
Date: Mon, 4 Sep 2017 11:35:38 +0800
Subject: [PATCH] add testcase for issue #1912

---
 .../java/com/alibaba/druid/sql/SQLUtils.java  | 12 +-----
 .../com/alibaba/druid/bvt/bug/Issue1912.java  | 41 +++++++++++++++++++
 2 files changed, 42 insertions(+), 11 deletions(-)
 create mode 100644 src/test/java/com/alibaba/druid/bvt/bug/Issue1912.java

diff --git a/src/main/java/com/alibaba/druid/sql/SQLUtils.java b/src/main/java/com/alibaba/druid/sql/SQLUtils.java
index ea809d4607..94fe2a33aa 100644
--- a/src/main/java/com/alibaba/druid/sql/SQLUtils.java
+++ b/src/main/java/com/alibaba/druid/sql/SQLUtils.java
@@ -696,12 +696,6 @@ public class SQLUtils {
         return SQLUtils.toSQLString(stmtList, dbType, null, null, tableMapping);
     }
 
-    public static boolean containsIndexDDL(String sql, String dbType) {
-        List<SQLStatement> stmtList = parseStatements(sql, dbType);
-
-        return false;
-    }
-
     public static long hash(String sql, String dbType) {
         Lexer lexer = SQLParserUtils.createLexer(sql, dbType);
 
@@ -871,10 +865,6 @@ public class SQLUtils {
         return false;
     }
 
-    public static SQLExpr decodeToCase(SQLMethodInvokeExpr x) {
-       return SQLTransformUtils.transformDecode(x);
-    }
-
     public static boolean replaceInParent(SQLExpr expr, SQLExpr target) {
         if (expr == null) {
             return false;
@@ -900,7 +890,7 @@ public class SQLUtils {
     }
 
     /**
-     * 重新排序建表语句
+     * 重新排序建表语句，解决建表语句的依赖关系
      * @param sql
      * @param dbType
      * @return
diff --git a/src/test/java/com/alibaba/druid/bvt/bug/Issue1912.java b/src/test/java/com/alibaba/druid/bvt/bug/Issue1912.java
new file mode 100644
index 0000000000..ce7c09114f
--- /dev/null
+++ b/src/test/java/com/alibaba/druid/bvt/bug/Issue1912.java
@@ -0,0 +1,41 @@
+package com.alibaba.druid.bvt.bug;
+
+import com.alibaba.druid.sql.SQLUtils;
+import com.alibaba.druid.sql.ast.SQLStatement;
+import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
+import com.alibaba.druid.sql.parser.SQLStatementParser;
+import com.alibaba.druid.sql.visitor.SQLASTOutputVisitor;
+import com.alibaba.druid.sql.visitor.SQLASTVisitor;
+import com.alibaba.druid.sql.visitor.SQLASTVisitorAdapter;
+import junit.framework.TestCase;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class Issue1912 extends TestCase {
+    public void test_for_issue() throws Exception {
+        String sql = "select a from t";
+        SQLStatementParser parser = new SQLStatementParser(sql);
+        SQLStatement stmt = parser.parseStatement();
+
+        final Map<String, String> columnMapping = new HashMap<String, String>();
+        columnMapping.put("a", "b");
+
+        SQLASTVisitor visitor = new SQLASTVisitorAdapter() {
+            public boolean visit(SQLIdentifierExpr x) {
+
+                String destColumn = columnMapping.get(x.getName());
+                if (destColumn != null) {
+                    x.setName(destColumn);
+                }
+
+                return super.visit(x);
+            }
+        };
+        stmt.accept(visitor);
+
+        assertEquals("SELECT b\n" +
+                "FROM t", SQLUtils.toSQLString(stmt));
+    }
+}