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Row Offset in SQL Server
... SELECT col1, col2, ROW_NUMBER() OVER (ORDER BY ID) AS RowNum
FROM MyTable
) AS MyDerivedTable
WHERE MyDerivedTable.RowNum BETWEEN @startRow AND @endRow
SQL Server 2000
Efficiently Paging Through Large Result Sets in SQL Server 2000
A More Efficient Method for Paging Through Large Result S...
Is a Java hashmap search really O(1)?
...r with average-case (expected) runtime. The former is indeed O(n) for hash tables in general (i.e. not using a perfect hashing) but this is rarely relevant in practice.
Any dependable hash table implementation, coupled with a half decent hash, has a retrieval performance of O(1) with a very small f...
SQL: capitalize first letter only [duplicate]
...a inside column? If its data you've to change, then use this:
UPDATE [yourtable]
SET word=UPPER(LEFT(word,1))+LOWER(SUBSTRING(word,2,LEN(word)))
If you just wanted to change it only for displaying and do not need the actual data in table to change:
SELECT UPPER(LEFT(word,1))+LOWER(SUBSTRING(word...
Difference between attr_accessor and attr_accessible
...hat when you create somehow a link between a (Rails) model with a database table, you NEVER, NEVER, NEVER need attr_accessor in your model to create setters and getters in order to be able to modify your table's records.
This is because your model inherits all methods from the ActiveRecord::Base Cl...
How to write a simple database engine [closed]
...f it). I know most of the basic data structures taught in CS (trees, hash tables, lists, etc.) as well as a pretty good understanding of compiler theory (and have implemented a very simple interpreter) but I don't understand how to go about writing a database engine. I have searched for tutorials ...
Lost my schema.rb! Can it be regenerated?
...lright. It simply holds a representation of the structure of your database tables. The data itself is not contained in this file.
To regenerate your schema.rb file, run:
bundle exec rake db:schema:dump
Then simply commit the new schema.rb file and you should be in good shape!
...
Import CSV file into SQL Server
...ll be
inserted with double quotes into rows.
after inserting the data into table you could replace those double quotes with ''.
update table
set columnhavingdoublequotes = replace(columnhavingdoublequotes,'"','')
3) How do we track if some rows have bad data, which import skips?
(does import...
How to vertically center a inside a div? [duplicate]
... @Blender Heh, though therein references a third option: display:table-cell; vertical-align:middle (along with a display:table-row parent). :) But no, you can be sure that I would never advocate using HTML table elements for layout.
– Phrogz
Dec 5 '10...
How to define a custom ORDER BY order in mySQL
...age,'ENU','JPN','DAN'), ID
Note however, that
It makes your SQL less portable, as other DBMSs might not have such function
When your list of languages (or other values to sort by) gets much longer, it's better to have a separate table with sortorder column for them, and join it to your queries fo...
querySelector and querySelectorAll vs getElementsByClassName and getElementById in JavaScript
...ements are live or static.
These concepts are summarized in the following table.
Function | Live? | Type | Time Complexity
querySelector | N | Element | O(n)
querySelectorAll | N | NodeList | O(n)
getElementById | Y | Element...
