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Difference between DateTime and Time in Ruby
...idually. This is a Ruby on Rails construct that serves as a wrapper around SQL-standard DATETIME fields. These contain arbitrary dates and can represent nearly any point in time as the range of expression is typically very large.
DateTime.new
# => Mon, 01 Jan -4712 00:00:00 +0000
So it's reass...
Troubleshooting “Illegal mix of collations” error in mysql
...the below error when trying to do a select through a stored procedure in MySQL.
16 Answers
...
Most useful NLog configurations [closed]
...etLogger("Database.Query");
Logger logger = LogManager.GetLogger("Database.SQL");
Logger logger = LogManager.GetLogger("Analysis.Financial");
Logger logger = LogManager.GetLogger("Analysis.Personnel");
Logger logger = LogManager.GetLogger("Analysis.Inventory");
And so on. With hierarchical logger...
Override Java System.currentTimeMillis for testing time sensitive code
...er compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes. Hibernate 5 & JPA 2.2 support java.time.
Where to obtain the java.time classes?
Java SE 8, Java SE 9, Java SE 10, Java SE 11, and later - Part of the standard Java API with a bundled implementation.
Java...
How can I pair socks from a pile efficiently?
...ately
This kind of recursive hash partitioning is actually being done by SQL Server when it needs to hash join or hash aggregate over huge data sets. It distributes its build input stream into many partitions which are independent. This scheme scales to arbitrary amounts of data and multiple CPUs ...
How do I pass variables and data from PHP to JavaScript?
... serialization format and JSON objects appear inside strings (kind of like SQL queries in server-side languages). However, in this answer the JSON method relies on the fact that most JSON objects are also valid JavaScript object so we write a JSON object into JavaScript code.
–...
Select first row in each GROUP BY group?
...
On Oracle 9.2+ (not 8i+ as originally stated), SQL Server 2005+, PostgreSQL 8.4+, DB2, Firebird 3.0+, Teradata, Sybase, Vertica:
WITH summary AS (
SELECT p.id,
p.customer,
p.total,
ROW_NUMBER() OVER(PARTITION BY p.customer
...
How exactly do Django content types work?
...ise" of sorts to bypass some of the rigid fundamentals of a table oriented SQL system. Do not prematurely optimize your app! Django is best at getting out of your way so you can write the next generation application you have always wanted: use it's features to your advantage!
...
What's the fastest way to merge/join data.frames in R?
...vels: a b c d e
> DF1
a b c
1 1 1 a
2 1 2 b
3 2 3 c
4 2 4 e
In the sqldf code that was posted in the question, it might appear that indexes were used on the two tables but, in fact, they are placed on tables which were overwritten before the sql select ever runs and that, in part, accounts f...
ServiceStack vs ASP.Net Web API [closed]
...uilt-in Mini Profiler (port of the excellent MVC Mini Profiler)
Includes Sql Profiling
JSON/JSONP, XML, JSV, CSV and SOAP end-points
The RestServiceBase and ServiceBase classes are intended to host your custom C# logic for maximum potential re-use as possible, e.g. Its DTO-first design triviall...