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How to use NULL or empty string in SQL
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Select *
From Table
Where (col is null or col = '')
Or
Select *
From Table
Where IsNull(col, '') = ''
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What is the difference between user and kernel modes in operating systems?
... the application with a private virtual address space and a private handle table. Because an application's virtual address space is private, one application cannot alter data that belongs to another application. Each application runs in isolation, and if an application crashes, the crash is limited ...
Correct use of Multimapping in Dapper
...rId.
There is a big caveat here, if the column ordering in the underlying table is flipped for some reason:
ProductID | ProductName | AccountOpened | CustomerName | CustomerId
--------------------------------------- -------------------------
splitOn: CustomerId will result in a null custo...
AWS MySQL RDS vs AWS DynamoDB [closed]
I've been using MySQL for a fair while now and I'm comfortable with its structure & SQL Queries etc.
4 Answers
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SQLite - UPSERT *not* INSERT or REPLACE
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Assuming three columns in the table: ID, NAME, ROLE
BAD: This will insert or replace all columns with new values for ID=1:
INSERT OR REPLACE INTO Employee (id, name, role)
VALUES (1, 'John Foo', 'CEO');
BAD: This will insert or replace 2 of the...
SQL Server: Difference between PARTITION BY and GROUP BY
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We can take a simple example.
Consider a table named TableA with the following values:
id firstname lastname Mark
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1 arun prasanth ...
How does MySQL process ORDER BY and LIMIT in a query?
...row.
select t.article
from
(select article, publish_date
from table1
order by publish_date desc limit 10) t
order by t.publish_date asc;
If you need all columns, it is done this way:
select t.*
from
(select *
from table1
order by publish_date desc limit 10) ...
Grant **all** privileges on database
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@Romain you are not really bringing alot to the table here - i don't name my users myuser - the questioner was simply using a username as an example - i used the same example username for consistency.
– diagonalbatman
Feb 16 '11 at 13...
CSS to make HTML page footer stay at bottom of the page with a minimum height, but not overlap the p
...w are 4 different methods of mine:
In each example the texts are freely-editable to illustrate how the content would render in different scenarios.
1) Flexbox
body{ height:100vh; margin:0; }
header{ min-height:50px; background:lightcyan; }
footer{ min-height:50px; background:PapayaWhip; }
/* ...
How to create CSV Excel file C#? [closed]
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Its best example...but how can i add two table in single file,means i have a one table of two rows and other table is 10 rows and both have unique column name.I want to add two rows table on top and after gap of two lines i want to add second table.
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