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Storing Images in PostgreSQL
... BLOB: "The SQL standard defines (...) BLOB. The input format is different from bytea, but the provided functions and operators are mostly the same",Manual.
EDIT 2014: I have not changed the original text above today (my answer was Apr 22 '12, now with 14 votes), I am opening the answer for your c...
Connecting overloaded signals and slots in Qt 5
...alueChanged(QString). From Qt 5.7, there are helper functions provided to select the desired overload, so you can write
connect(spinbox, qOverload<int>(&QSpinBox::valueChanged),
slider, &QSlider::setValue);
For Qt 5.6 and earlier, you need to tell Qt which one you want to p...
MVC pattern on Android
...e (I believe many Android devs see it that way) why not talk to your views from the Activity?
– user1545072
Oct 1 '13 at 7:19
8
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SQL Server String or binary data would be truncated
...ur source query and execute Max(Len( source col )) on each column. I.e.,
Select Max(Len(TextCol1))
, Max(Len(TextCol2))
, Max(Len(TextCol3))
, ...
From ...
Then compare those lengths to the data type lengths in your destination table. At least one, exceeds its destination column leng...
Intent - if activity is running, bring it to front, else start a new one (from notification)
... Activity pair. I want to display the Activity instance if I get a message from it. Is there any way of doing this. eg: HashMap.get(Messenger).bringActivityToFront(); I mean, the activity is still running. If I open recent task and click it, it will onResume(); Cant I onResume() programatically.
...
Print number of keys in Redis
...
You can issue the INFO command, which returns information and statistics about the server. See here for an example output.
As mentioned in the comments by mVChr, you can use info keyspace directly on the redis-cli.
redis> INFO
# Server
redis_version...
SQL Server IN vs. EXISTS Performance
...execution operation, to get their results.
An example:
Query 1 ( plan )
select * from dt where dt.customer in (select c.code from customer c where c.active=0)
Query 2 ( plan )
select * from dt where exists (select 1 from customer c where c.code=dt.customer and c.active=0)
...
Cannot issue data manipulation statements with executeQuery()
...() to issue data manipulation statements. executeQuery() is only meant for SELECT queries (i.e. queries that return a result set).
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Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause?
...pdated) values(null, null);
Query OK, 1 row affected (0.06 sec)
mysql> select * from t5;
+----+---------------------+---------------------+
| id | stamp_created | stamp_updated |
+----+---------------------+---------------------+
| 2 | 2009-04-30 09:44:35 | 2009-04-30 09:44:35 |
+...
What do the makefile symbols $@ and $< mean?
...
From Managing Projects with GNU Make, 3rd Edition, p. 16 (it's under GNU Free Documentation License):
Automatic variables are set by make after a rule is matched. They
provide access to elements from the target and prer...