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SQL - Rounding off to 2 decimal places
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@Ram The question didn't specify the sql server engine - which is why i highlighted the round v cast on its own. The convert to numeric doesn't do rounding in all engines so if the calculated number was 10.809 you would get 10.80 rather than the 10.81 the questi...
PostgreSQL: How to pass parameters from command line?
...ses ? placeholders. I wanted to test this same query directly from the psql command line (outside the script). I want to avoid going in and replacing all the ? with actual values, instead I'd like to pass the arguments after the query.
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How to get min/max of two integers in Postgres/SQL?
How do I find the maximum (or minimum) of two integers in Postgres/SQL? One of the integers is not a column value.
2 Answer...
Why all the Active Record hate? [closed]
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end
people = Person.find(:all, :include => :company )
This generates SQL with LEFT JOIN companies on companies.id = person.company_id, and automatically generates associated Company objects so you can do people.first.company and it doesn't need to hit the database because the data is already p...
Using IQueryable with Linq
...t;= 25.00);
The code looks the same, but the difference here is that the SQL executed will be SELECT * FROM Products WHERE Cost >= 25.
From your POV as a developer, this looks the same. However, from a performance standpoint, you may only return 2 records across the network instead of 20,000....
UCenter实现各系统通信的原理 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...查用户id变量$discuz_uid是否为空来判断，用户是否登录（包括从别的应用登录。）
如果用户从bbs登录，则在登录验证成功后通过如下代码：
$ucsynlogin = $allowsynlogin ? uc_user_synlogin($discuz_uid) : '';
通知其它应用----“用户已从bbs登...
SQL JOIN - WHERE clause vs. ON clause
After reading it, this is not a duplicate of Explicit vs Implicit SQL Joins .
The answer may be related (or even the same) but the question is different.
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Change Oracle port from port 8080
...nvironmental variables are set correctly start with the following:
C:\>sqlplus /nolog
SQL*Plus: Release 10.2.0.1.0 - Production on Tue Aug 26 10:40:44 2008
Copyright (c) 1982, 2005, Oracle. All rights reserved.
SQL> connect
Enter user-name: system
Enter password: <enter password if will ...
SQL Add foreign key to existing column
If I am using the following SQL command in SQL Server 2008 to update a table with a foreign key constraint:
6 Answers
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The specified type member 'Date' is not supported in LINQ to Entities Exception
...not translate most .NET Date methods (including the casting you used) into SQL since there is no equivalent SQL.
The solution is to use the Date methods outside the LINQ statement and then pass in a value. It looks as if Convert.ToDateTime(rule.data).Date is causing the error.
Calling Date on a Da...