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PostgreSQL - max number of parameters in “IN” clause?
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explain select * from test where id in (values (1), (2));
QUERY PLAN
Seq Scan on test (cost=0.00..1.38 rows=2 width=208)
Filter: (id = ANY ('{1,2}'::bigint[]))
But if try 2nd query:
explain select * from test where id = an...
Convert string[] to int[] in one line of code using LINQ
...you would need the extra ToArray call to get an array:
int[] myInts = arr.Select(int.Parse).ToArray();
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How do you configure an OpenFileDialog to select folders?
In VS .NET, when you are selecting a folder for a project, a dialog that looks like an OpenFileDialog or SaveFileDialog is displayed, but is set up to accept only folders. Ever since I've seen this I've wanted to know how it's done. I am aware of the FolderBrowserDialog, but I've never really like...
How to execute raw SQL in Flask-SQLAlchemy app
...xecute("<sql here>")
or:
from sqlalchemy import text
sql = text('select name from penguins')
result = db.engine.execute(sql)
names = [row[0] for row in result]
print names
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How to get the client IP address in PHP [duplicate]
...the IP to a database as a string, make sure you have space for at least 45 characters. IPv6 is here to stay and those addresses are larger than the older IPv4 addresses.
(Note that IPv6 usually uses 39 characters at most but there is also a special IPv6 notation for IPv4 addresses which in its full...
Professional jQuery based Combobox control? [closed]
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If I already select one value, then click arrow it only show the selected value, not all value.
– linbo
Oct 10 '12 at 11:55
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Invalid postback or callback argument. Event validation is enabled using '
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I had an experience with DataGrid. One of it's columns was "Select" button. When I was clicking "Select" button of any row I had received this error message:
"Invalid postback or callback argument. Event validation is enabled using in configuration or
<%@ Page EnableEve...
Swapping two variable value without using third variable
...y){
int t;
t = *y;
*y = *x;
*x = t;
}
int main(int argc, char* argv[]){
int x = 4;
int y = 5;
int z = pow(2,28);
while ( z-- ){
# ifdef USE_XOR
xorSwap(&x,&y);
# else
tempSwap(&x, &y);
# endif
}
retu...
Reason for Column is invalid in the select list because it is not contained in either an aggregate f
...c
1 def
1 ghi
2 jkl
2 mno
2 pqr
And I do the following query:
SELECT a, b
FROM T
GROUP BY a
The output should have two rows, one row where a=1 and a second row where a=2.
But what should the value of b show on each of these two rows? There are three possibilities in each case, and no...
Select multiple columns in data.table by their numeric indices
How can we select multiple columns using a vector of their numeric indices (position) in data.table ?
5 Answers
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