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How to flatten nested objects with linq expression
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myBooks.SelectMany(b => b.Chapters
.SelectMany(c => c.Pages
.Select(p => b.Name + ", " + c.Name + ", " + p.Name)));
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Is the NOLOCK (Sql Server hint) bad practice?
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With NOLOCK hint, the transaction isolation level for the SELECT statement is READ UNCOMMITTED. This means that the query may see dirty and inconsistent data.
This is not a good idea to apply as a rule. Even if this dirty read behavior is OK for your mission critical web based app...
ORACLE 常用日期函数 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...的日期。如果给出一负数，返回值日期之前几个月日期。select add_months(to_date(&...ADD_MONTHS函数在输入日期上加上指定的几个月返回一个新的日期。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','yyyymmd...
Get table name by constraint name [duplicate]
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SELECT owner, table_name
FROM dba_constraints
WHERE constraint_name = <<your constraint name>>
will give you the name of the table. If you don't have access to the DBA_CONSTRAINTS view, ALL_CONSTRAINTS or US...
Build an iOS app without owning a mac? [closed]
...r virtual machine (the name is unimportant, I called it "Mac"). In "Type", select "Mac OS X" and in "Version" select "macOS 10.13 High Sierra (64 bit)" (the Mac version you will install on the virtual machine is actually Catalina, but VirtualBox doesn't have that option yet and it works just fine if...
Naming of ID columns in database tables
...!)and forget to change the alias in the join condition.
So you now have
select t1.field1, t2.field2, t3.field3
from table1 t1
join table2 t2 on t1.id = t2.table1id
join table3 t3 on t1.id = t3.table2id
when you meant
select t1.field1, t2.field2, t3.field3
from table1 t1
join table2 t2 on t1...
How do I select a random value from an enumeration?
Given an arbitrary enumeration in C#, how do I select a random value?
9 Answers
9
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Is it possible to insert multiple rows at a time in an SQLite database?
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This can be recast into SQLite as:
INSERT INTO 'tablename'
SELECT 'data1' AS 'column1', 'data2' AS 'column2'
UNION ALL SELECT 'data1', 'data2'
UNION ALL SELECT 'data1', 'data2'
UNION ALL SELECT 'data1', 'data2'
a note on performance
I originally used this technique to efficiently lo...
How can I shift-select multiple checkboxes like GMail?
... can click on one checkbox in the email list, hold down the Shift key, and select a second checkbox. The JavaScript will then select/unselect the checkboxes that are between the two checboxes.
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How to get the Full file path from URI
...but if i do it like the MediaStore Solution, it won't work if the app user selects eg Astro as browser, instead of Music Player. How do I solve this?
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