在表条件子句中转义特殊字符#

时间:2013-04-12 14:25:40

标签: java android escaping special-characters android-sqlite

在SQLite中创建包含特殊字符#的列名的表。

不知道如何逃避这一点,以便SQLite识别它。

我发现#的转义码是%23。所以我试着这样做:

condition = condition.replace("usernum#", "usernum%23");

其中condition是string类型的SQLite条件,例如select * from users where id = '2' ORDER BY usernum#

但上面的方法是给出SQLite异常。

LOG:

04-12 20:00:44.395: E/AndroidRuntime(8054): android.database.sqlite.SQLiteException: no such column: usernum (code 1): , while compiling: select * from Users WHERE id !=1 order by Type DESC, usernum%23 ASC

错误在这一行:

Cursor curr = db.rawQuery("select " + fields + " from " + table + " "+ condition, null);

1 个答案:

答案 0 :(得分:0)

  

04-12 20:00:44.395:E / AndroidRuntime(8054):   android.database.sqlite.SQLiteException:没有这样的列:usernum(代码   1):,同时编译:select * from Users WHERE id!= 1 order by Type   DESC,usernum%23 ASC

由于列包含特殊字符,解决方案是将其包装为双引号(整列)并且它将起作用

select * from test order by "username#" desc;

在你的情况下:

String query = "Select * from users where id = ? ORDER BY \"usernum#\"";
Cursor c = db.rawQuery(query, new String[] {String.valueOf(id)});

使用query()方法的解决方案:

String[] columns = {...};
String selection = idColumn + " = ?";
String[] args = {String.valueOf(id)};
String orderBy = "\"" + orderByColumn + "\"";
Cursor c = db.query(table, columns, selection, args, null, null, orderBy);