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What makes a SQL statement sargable?
...non-sargable is to include a field inside a function in the where clause:
SELECT ... FROM ...
WHERE Year(myDate) = 2008
The SQL optimizer can't use an index on myDate, even if one exists. It will literally have to evaluate this function for every row of the table. Much better to use:
WHERE myDat...
SQL Server Profiler - How to filter trace to only display events from one database?
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Under Trace properties > Events Selection tab > select show all columns. Now under column filters, you should see the database name. Enter the database name for the Like section and you should see traces only for that database.
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Select the values of one property on all objects of an array in PowerShell
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I think you might be able to use the ExpandProperty parameter of Select-Object.
For example, to get the list of the current directory and just have the Name property displayed, one would do the following:
ls | select -Property Name
This is still returning DirectoryInfo or FileInfo obje...
mongodb: insert if not exists
...what data you want to write:
data = {"$set":{"key2":"value2"}}
Now your selected document will update the value of "key2" only and leave everything else untouched.
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Set selected item of spinner programmatically
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Use the following:
spinnerObject.setSelection(INDEX_OF_CATEGORY2).
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Export specific rows from a PostgreSQL table as INSERT SQL script
...d line utility pg_dump to export to a file:
create table export_table as
select id, name, city
from nyummy.cimory
where city = 'tokyo'
$ pg_dump --table=export_table --data-only --column-inserts my_database > data.sql
--column-inserts will dump as insert commands with column names.
--data-...
Is it possible to select the last n items with nth-child?
Using a standard list, I'm trying to select the last 2 list items. I've various permutations of An+B but nothing seems to select the last 2:
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Get selected subcommand with argparse
When I use subcommands with python argparse, I can get the selected arguments.
2 Answers
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Solving “The ObjectContext instance has been disposed and can no longer be used for operations that
... to find out where the reference is or isn't set, right-click its name and select "Find All References". You can then place a breakpoint at every location that requests data, and run your program with the debugger attached. Every time the debugger breaks on such a breakpoint, you need to determine w...
More elegant “ps aux | grep -v grep”
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@kxsong: | grep '[t]erminal' selects any line containing the word 'terminal' without putting the word 'terminal' into the process list. What are you trying to achieve with | grep '[r]oot' and how is it not working? There is likely to be a better solution...