我想知道JMS API是否使用任何协议来传输消息,或者是否使用它自己的协议.如果是前者,哪个协议?
我通过网络阅读了很多文章,但我找不到答案.
我有以下查询.由于其中的子查询,这会降低性能.我尝试了很多来添加Join而不是Subquery.但是徒劳无功 任何人都可以告诉我如何使用JOIN重写此查询?
update Table_1
set status = 'Status_2'
where status ='status_1' and (col_1, col_2, col_3, nvl(col_4,0), col_5) in (
select col_1, col_2, col_3, nvl(col_4,0), col_5 from Table_2 where status ='Status_0');
Run Code Online (Sandbox Code Playgroud)
请看SELECT * FROM table(DBMS_XPLAN.Display);下面的内容
Plan hash value: 1290346170
------------------------------------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
------------------------------------------------------------------------------------------------------
| 0 | UPDATE STATEMENT | | 1 | 376 | 456 (3)| 00:00:06 |
| 1 | UPDATE | Table_1 | | …Run Code Online (Sandbox Code Playgroud) 我试图在我的应用程序中显示通话记录详细信息,但 CallLog.Calls.CACHED_NAME 对于某些联系人始终返回 null,即使它是已保存的带有姓名的联系人。内置通话记录正确显示这些联系人的姓名。
这是我的代码:
protected customAdapRecent doInBackground(Void... params) {
ContentResolver resolver = context.getContentResolver();
final String[] PROJECTION = new String[] {
// CallLog.Calls.CACHED_LOOKUP_URI,
CallLog.Calls.NUMBER,
CallLog.Calls.CACHED_NAME,
CallLog.Calls.TYPE,
CallLog.Calls.DATE,
CallLog.Calls.DURATION
};
Cursor cursor = resolver.query(CallLog.Calls.CONTENT_URI, PROJECTION, null, null, CallLog.Calls.DATE + " DESC");
if(cursor.getCount() > 0)
{
int iNumber = cursor.getColumnIndex(CallLog.Calls.NUMBER);
int iName = cursor.getColumnIndex(CallLog.Calls.CACHED_NAME);
int iType = cursor.getColumnIndex(CallLog.Calls.TYPE);
int iDate = cursor.getColumnIndex(CallLog.Calls.DATE);
int iDuration = cursor.getColumnIndex(CallLog.Calls.DURATION);
DateFormat datePattern = DateFormat.getDateInstance(DateFormat.FULL);
String number;
String name;
String type;
String date;
String duration;
String contactId; …Run Code Online (Sandbox Code Playgroud)