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PG undefinedtable error relation users does not exist
...r, and upon my research, found out that one of the reasons for PG undefinedtable error relation users does not exist error is:
This error is a migration error. You may have created new model with some database attributes. After creating model you have to migrate attributes to your rails app schema....
In HTML I can make a checkmark with ✓ . Is there a corresponding X-mark?
...nks. any idea where I can get a reference for these like the ascii lookup tables?
– nc.
Apr 3 '09 at 0:35
1
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How do I get the type of a variable?
...ot caterpillars. (When you create an database application to open variable tables from 'unknown' databases you need to control field type to variable scheme and vice vera in a 'very' dymanic way ;) )
– TomeeNS
Sep 20 '17 at 14:02
...
Show/hide 'div' using JavaScript
...u would still like the element to occupy space (like if you were to hide a table cell), you could change the element's visibility property instead:
element.style.visibility = 'hidden'; // Hide
element.style.visibility = 'visible'; // Show
Hiding a collection of elements:
If you want to ...
How to set breakpoints on future shared libraries with a command flag
...
With no symbols.
objdump -t /lib/libacl.so
SYMBOL TABLE:
no symbols
objdump -T /lib/libacl.so
...
00002bd0 g DF .text 000000d0 ACL_1.0 acl_delete_entry
...
(gdb) break 0x0002bd0
(gdb) x/20i acl_delete_entry
0x2bd0 <acl_delete_entry>: stwu r1,-32(r1...
Rolling or sliding window iterator?
...I changed it to individually look up and add items in a window of ten, the tables turned and the tee method was 20% faster. I was able to recover some speed by using negative indexes for the last five terms in the addition, but tee was still a little faster. Overall I would estimate that either one ...
Why does multiprocessing use only a single core after I import numpy?
... the answer here.
It turns out that certain Python modules (numpy, scipy, tables, pandas, skimage...) mess with core affinity on import. As far as I can tell, this problem seems to be specifically caused by them linking against multithreaded OpenBLAS libraries.
A workaround is to reset the task af...
Where IN clause in LINQ [duplicate]
...nClause = new string[] {"One", "Two", "Three"};
var results = from x in MyTable
where myInClause.Contains(x.SomeColumn)
select x;
// OR
var results = MyTable.Where(x => myInClause.Contains(x.SomeColumn));
In the case of your query, you could do something like this.....
How can I use PowerShell with the Visual Studio Command Prompt?
...output of cmd.exe. We also ask cmd.exe to output
## the environment table after the batch file completes
cmd.exe /c " `"$Path`" $Parameters && set > `"$tempFile`" "
## Go through the environment variables in the temp file.
## For each of them, set the variable in our...
Rails 3 execute custom sql query without a model
...
Maybe try this:
ActiveRecord::Base.establish_connection(...)
ActiveRecord::Base.connection.execute(...)
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