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MySQL indexes - what are the best practices?
...going on.
Broadly speaking, an index imposes an ordering on the rows of a table.
For simplicity's sake, imagine a table is just a big CSV file. Whenever a row is inserted, it's inserted at the end. So the "natural" ordering of the table is just the order in which rows were inserted.
Imagine y...
How to show multiline text in a table cell
I want to show a paragraph from database into a table cell.
10 Answers
10
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How do I vertically align text in a div?
...solution.html
Article summary:
For a CSS 2 browser, one can use display:table/display:table-cell to center content.
A sample is also available at JSFiddle:
div { border:1px solid green;}
<div style="display: table; height: 400px; overflow: hidden;">
<div style="display: table-c...
PreparedStatement IN clause alternatives?
...lable here.
The suggested options are:
Prepare SELECT my_column FROM my_table WHERE search_column = ?, execute it for each value and UNION the results client-side. Requires only one prepared statement. Slow and painful.
Prepare SELECT my_column FROM my_table WHERE search_column IN (?,?,?) and exe...
What are database normal forms and can you give examples? [closed]
...y normalization, which is a process of organizing columns (attributes) and tables (relations) to reduce data redundancy and improve data integrity. (as written on Wikipedia ).
...
Make div (height) occupy parent remaining height
...: calc( 100% - 100px ); }
It is pretty widely supported, with the only notable exceptions being <= IE8 or Safari 5 (no support) and IE9 (partial support). Some other issues include using calc in conjunction with transform or box-shadow, so be sure to test in multiple browsers if that is of conc...
How Do I Choose Between a Hash Table and a Trie (Prefix Tree)?
So if I have to choose between a hash table or a prefix tree what are the discriminating factors that would lead me to choose one over the other. From my own naive point of view it seems as though using a trie has some extra overhead since it isn't stored as an array but that in terms of run time (a...
SQL JOIN - WHERE clause vs. ON clause
...r join has taken place.
b. ON clause - Before joining. Records (from right table) will be filtered before joining. This may end up as null in the result (since OUTER join).
Example: Consider the below tables:
1. documents:
| id | name |
--------|-------------|
| 1 ...
conditional unique constraint
...unt > 0.
http://msdn.microsoft.com/en-us/library/ms188258.aspx
CREATE TABLE CheckConstraint
(
Id TINYINT,
Name VARCHAR(50),
RecordStatus TINYINT
)
GO
CREATE FUNCTION CheckActiveCount(
@Id INT
) RETURNS INT AS BEGIN
DECLARE @ret INT;
SELECT @ret = COUNT(*) FROM CheckConstraint WHER...
Best way to get identity of inserted row?
...
@@IDENTITY returns the last identity value generated for any table in the current session, across all scopes. You need to be careful here, since it's across scopes. You could get a value from a trigger, instead of your current statement.
SCOPE_IDENTITY() returns the last identity val...