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Get properties and values from unknown object
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Here's something I use to transform an IEnumerable<T> into a DataTable that contains columns representing T's properties, with one row for each item in the IEnumerable:
public static DataTable ToDataTable<T>(IEnumerable<T> items)
{
var table = CreateDataTableForPropertiesO...
What is a NullReferenceException, and how do I fix it?
...that C# has the concept of nullable datatypes for variables (like database tables can have nullable fields) - you can assign null to them to indicate there is no value stored in it, for example int? a = null; where the question mark indicates it is allowed to store null in variable a. You can check ...
PostgreSQL - fetch the row which has the Max value for a column
I'm dealing with a Postgres table (called "lives") that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id
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Frequency table for a single variable
One last newbie pandas question for the day: How do I generate a table for a single Series?
4 Answers
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How can I convert bigint (UNIX timestamp) to datetime in SQL Server?
...ved simply as: select dbo.fn_ConvertToDateTime( src_column/1000 ) from src_table;
– access_granted
Jan 10 '19 at 4:42
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show 2 more comments...
How to create a printable Twitter-Bootstrap page
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Bootstrap 3.2 update: (current release)
Current stable Bootstrap version is 3.2.0.
With version 3.2 visible-print deprecated, so you should use like this:
Class Browser Print
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.visible-print-block ...
Why malloc+memset is slower than calloc?
...n parts here: your program, the standard library, the kernel, and the page tables. You already know your program, so...
Memory allocators like malloc() and calloc() are mostly there to take small allocations (anything from 1 byte to 100s of KB) and group them into larger pools of memory. For exam...
Secure hash and salt for PHP passwords
... etc, can actually reduce entropy by making the password scheme more predictable. I do agree. Randomess, as truly random as possible, is always the safest but least memorable solution.
So far as I've been able to tell, making the world's best password is a Catch-22. Either its not memorable, too pr...
How do I copy SQL Azure database to my local development server?
...Using SSIS (SQL Server Integration Services). It only imports data in your table. Column properties, constraints, keys, indices, stored procedures, triggers, security settings, users, logons, etc. are not transferred. However it is very simple process and can be done simply by going through wizard i...
How to delete all data from solr and hbase
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This answer discusses how to delete all the tables in hbase: stackoverflow.com/questions/3990952/…. If you want to just delete the data in the table, you can truncate them rather than drop them.
– codingFoo
Nov 30 '11 at 23:13...