我想在查询中创建新表，并在最后使用它们进行最终查询。我不记得语法是什么，无法在任何地方找到它。 （这里只是一个基本的例子）。
phones as
(
SELECT phone_number from customers
)
emails as
(
SELECT emails from customers
)
// do something with both
答案 0 :(得分：6)
您正在寻找with phones as (
SELECT phone_number from customers
),
emails as (
SELECT emails from customers
)
select . . .;
CTE's答案 1 :(得分：2)
您正在寻找通用表格表达式（CTE）。这些是使用public void takePhoto() {
Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
File folder = new File(Environment.getExternalStorageDirectory() + "/PhotoBox");
if (!folder.exists()) {
folder.mkdir();
}
final Calendar c = Calendar.getInstance();
String new_Date = c.get(Calendar.DAY_OF_MONTH) + "-" + ((c.get(Calendar.MONTH)) + 1) + "-" + c.get(Calendar.YEAR) + " " + c.get(Calendar.HOUR) + "-" + c.get(Calendar.MINUTE) + "-" + c.get(Calendar.SECOND);
path = String.format(Environment.getExternalStorageDirectory() + "/" + "PhotoBox" + "/%s.png", "Product(" + new_Date + ")");
File photo = new File(path);
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(photo));
xPath = path;
startActivityForResult(intent, 2);
}
：
with您的示例选择似乎并不特别有用，但我认为它们仅用于说明。