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PostgreSQL ERROR: canceling statement due to conflict with recovery
... will be canceled more often.
You can work around this by starting a repeatable read transaction on primary which does a dummy query and then sits idle while a real query is run on secondary. Its presence will prevent vacuuming of old row versions on primary.
More on this subject and other workaro...
Can I use GDB to debug a running process?
...so use the "file" command
to specify the program, and to load its symbol table.
NOTE: You may have difficulty attaching to a process due to improved security in the Linux kernel - for example attaching to the child of one shell from another.
You'll likely need to set /proc/sys/kernel/yama/ptr...
Convert a matrix to a 1 dimensional array
...dimensions of the matrix/array.
Elts_int <- as.matrix(tmp_int) # read.table returns a data.frame as Brandon noted
dim(Elts_int) <- (maxrow_int*maxcol_int,1)
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When to use Storyboard and when to use XIBs
... need XIBs: In both of my Storyboard projects I had to use XIBs for custom table cells.
I think Storyboards are a step in the right direction for UI implementation and hope Apple will extend them in future iOS versions. They need to resolve the "single file" issue though, otherwise they won't be a...
Convert data.frame column to a vector?
... of using the '[[' operator is that it works both with data.frame and data.table. So if the function has to be made running for both data.frame and data.table, and you want to extract a column from it as a vector then
data[["column_name"]]
is best.
...
Do Facebook Oauth 2.0 Access Tokens Expire?
...rd.
Assume you store the user's facebook uid and access token in a users table in your database,every time the user clicks on the "Login with facebook" button, you check the login statususing facebook Javascript API, and then examine the connection status from the response,if the user has connecte...
Why Qt is misusing model/view terminology?
...del you are using (own model subclass: probably within the model; e.g. QSqlTableModel: outside (but maybe cached within) the model). To put your models and views together, use own classes which then implement the business logic.
Long answer
Qt's model/view approach and terminology:
Qt provides ...
Returning IEnumerable vs. IQueryable
... approximately takes 90 seconds to run that block of code against a WebLog table which has 1 million records.
So, all table records are loaded into memory as objects, and then with each .Where() it will be another filter in memory against these objects.
When we use IQueryable instead of IEnumerabl...
Reading/writing an INI file
...g ways:
// Creates or loads an INI file in the same directory as your executable
// named EXE.ini (where EXE is the name of your executable)
var MyIni = new IniFile();
// Or specify a specific name in the current dir
var MyIni = new IniFile("Settings.ini");
// Or specify a specific name in a speci...
Using awk to remove the Byte-order mark
...
-- ADDENDUM --
Unicode Byte Order Mark (BOM) FAQ includes the following table listing the exact BOM bytes for each encoding:
Bytes | Encoding Form
--------------------------------------
00 00 FE FF | UTF-32, big-endian
FF FE 00 00 | UTF-32, little-endian
FE FF | UTF-16, b...