Java Android向数据库查询添加变量
我有一段代码不起作用。谁能告诉我我做错了什么Java Android向数据库查询添加变量,java,android,database,Java,Android,Database,我有一段代码不起作用。谁能告诉我我做错了什么 String option = names.getText().toString(); Cursor c = db.rawQuery("SELECT * from numbers Where fname=option", null); 更改如下: Cursor c = db.rawQuery("SELECT * from numbers Where fname='"+option+"' ", null); 试试这个 Strin
String option = names.getText().toString();
Cursor c = db.rawQuery("SELECT * from numbers Where fname=option", null);
更改如下:
Cursor c = db.rawQuery("SELECT * from numbers Where fname='"+option+"' ", null);
试试这个
String query = "SELECT * from numbers Where fname='"+ option +"'";
database.execSQL(query);
喜欢使用带有
?
占位符的准备好的语句
String option = names.getText().toString();
String query = "SELECT * from numbers Where fname = ?"
Cursor c = db.rawQuery(query, new String[] {option});
“从数字中选择*,其中fname=“+选项