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LINQ - Full Outer Join
...rst.ID equals last.ID into temp
from last in temp.DefaultIfEmpty()
select new
{
first.ID,
FirstName = first.Name,
LastName = last?.Name,
};
var rightOuterJoin =
from last in lastNames
join first in firstNames on last.ID equals first.ID into temp
fr...
SQLite - UPSERT *not* INSERT or REPLACE
... (id, role, name)
VALUES ( 1,
'code monkey',
(SELECT name FROM Employee WHERE id = 1)
);
This will update 2 of the columns.
When ID=1 exists, the ROLE will be unaffected.
When ID=1 does not exist, the role will be set to 'Benchwarmer' instead of the default v...
ORACLE 常用日期函数 - ORACLE - 清泛IT论坛，有思想、有深度
...日期。如果给出一负数，返回值日期之前几个月日期。
select add_months(to_date('20150201','yyyymmdd'), -1) from dual
结果：2015/1/1
相应的，加减天数add_days函数是不存在的，直接用+、-即可，例如：
select to_date('20150201','yyyymmdd')+1 from dual
...
Extract a dplyr tbl column as a vector
...2 3.62 3.54 4.11
A nice way to do this in v0.2 of dplyr:
iris2 %>% select(Species) %>% collect %>% .[[5]]
Or if you prefer:
iris2 %>% select(Species) %>% collect %>% .[["Species"]]
Or if your table isn't too big, simply...
iris2 %>% collect %>% .[["Species"]]
...
PostgreSQL query to return results as a comma separated list
Let say you have a SELECT id from table query (the real case is a complex query) that does return you several results.
5 ...
Parameterize an SQL IN clause
...
Here's a quick-and-dirty technique I have used:
SELECT * FROM Tags
WHERE '|ruby|rails|scruffy|rubyonrails|'
LIKE '%|' + Name + '|%'
So here's the C# code:
string[] tags = new string[] { "ruby", "rails", "scruffy", "rubyonrails" };
const string cmdText = "select * from t...
How to add ASP.NET 4.0 as Application Pool on IIS 7, Windows 7
...t to Windows 7.
One of the things that I need to run the application is to select ASP.NET v4.0 as the application pool within IIS.
...
How can I get column names from a table in Oracle?
...
You can query the USER_TAB_COLUMNS table for table column metadata.
SELECT table_name, column_name, data_type, data_length
FROM USER_TAB_COLUMNS
WHERE table_name = 'MYTABLE'
share
|
improve ...
Spring JPA @Query with LIKE
...
Try to use the following approach (it works for me):
@Query("SELECT u.username FROM User u WHERE u.username LIKE CONCAT('%',:username,'%')")
List<String> findUsersWithPartOfName(@Param("username") String username);
Notice: The table name in JPQL must start with a capital letter...
How to change an Eclipse default project into a Java project
.... Taking a backup is very recommended!
How to do it just using Eclipse?
Select project.
Open the project properties through Project -> Properties.
Go to "Targetted Runtimes" and add the proper runtime. Click APPLY.
Go to "Project Facets" and select the JAVA facet which has appeared due to step...