大约有 47,000 项符合查询结果（耗时：0.0797秒） [XML]
Running PostgreSQL in memory only
...atement = ds.getConnection().createStatement();
statement.execute("SELECT 1");
ResultSet resultSet = statement.getResultSet();
resultSet.next();
int resultSetInt = resultSet.getInt(1);
assertEquals("A basic SELECT query succeeds", 1, resultSetInt);
}
}
...
How to join (merge) data frames (inner, outer, left, right)
...s these operations in SQL.
library(sqldf)
## inner join
df3 <- sqldf("SELECT CustomerId, Product, State
FROM df1
JOIN df2 USING(CustomerID)")
## left join (substitute 'right' for right join)
df4 <- sqldf("SELECT CustomerId, Product, State
FROM df1...
Convert list of dictionaries to a pandas DataFrame
...o extract only the 0th and 2nd rows from data2 above, you can use:
rows_to_select = {0, 2}
for i in reversed(range(len(data2))):
if i not in rows_to_select:
del data2[i]
pd.DataFrame(data2)
# pd.DataFrame.from_dict(data2)
# pd.DataFrame.from_records(data2)
A B C D E
0 5...
How can I save an image to the camera roll?
... app and they can be viewed as small thumbnails. When a small thumbnail is selected it goes to a new view and a fullscreen version can be viewed. I have a button in the right corner of the top nav that says "save" and this is the button that I wish to save the image to the device's cameral roll so t...
Attach IntelliJ IDEA debugger to a running Java process
...ation:
Run -> Edit Configurations...
Click the "+" in the upper left
Select the "Remote" option in the left-most pane
Choose a name (I named mine "remote-debugging")
Click "OK" to save:
JVM Options
The configuration above provides three read-only fields. These are options that tell the JV...
How to flatten tree via LINQ?
...IEnumerable<MyNode> Flatten(IEnumerable<MyNode> e) =>
e.SelectMany(c => Flatten(c.Elements)).Concat(new[] { e });
You can then filter by group using Where(...).
To earn some "points for style", convert Flatten to an extension function in a static class.
public static IEnume...
How do I flush the PRINT buffer in TSQL?
...y the following;
-- Replace PRINT function
DECLARE @strMsg NVARCHAR(100)
SELECT @strMsg = 'Here''s your message...'
RAISERROR (@strMsg, 0, 1) WITH NOWAIT
OR
RAISERROR (n'Here''s your message...', 0, 1) WITH NOWAIT
sha...
Why does SSL handshake give 'Could not generate DH keypair' exception?
...DHE_.... The later would happen if I added BouncyCastle. If TLS_ECDHE_ was selected, MOST OF the time it worked, but not ALWAYS, so adding even BouncyCastle provider was unreliable (failed with same error, every other time or so). I guess somewhere in the Sun SSL implementation sometimes it choose D...
ng-repeat finish event
...
Beautiful, this did the job. I wanted to auto-select text in a textbox, and the timeout did the trick. Otherwise, the {{model.value}} text got selected and then deselected when the data-bound model.value was injected.
– JoshGough
Ma...
What is the point of Lookup?
...in those assemblies
IEnumerable<Type> allTypes = sampleTypes.Select(t => t.Assembly)
.SelectMany(a => a.GetTypes());
// Grouped by namespace, but indexable
ILookup<string, Type> lookup = allTypes.ToLookup(t =&g...