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SQL/mysql - Select distinct/UNIQUE but return all columns?
...
You're looking for a group by:
select *
from table
group by field1
Which can occasionally be written with a distinct on statement:
select distinct on field1 *
from table
On most platforms, however, neither of the above will work because the behavior on the other co...
space between divs - display table-cell
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You can use border-spacing property:
HTML:
<div class="table">
<div class="row">
<div class="cell">Cell 1</div>
<div class="cell">Cell 2</div>
</div>
</div>
CSS:
.table {
display: table;
border-collapse: ...
Any way to select without causing locking in MySQL?
...h-nolock.aspx
in MS SQL Server you would do the following:
SELECT * FROM TABLE_NAME WITH (nolock)
and the MYSQL equivalent is
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED ;
SELECT * FROM TABLE_NAME ;
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ ;
EDIT
Michael Mior sugg...
Converting string from snake_case to CamelCase in Ruby
...ring:
"AppUser".underscore # => "app_user"
or, if you want to get the table name, which is probably why you'd want the snake case:
AppUser.name.tableize # => "app_users"
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How to 'insert if not exists' in MySQL?
I started by googling, and found this article which talks about mutex tables.
10 Answers
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updating table rows in postgres using subquery
Using postgres 8.4, My goal is to update existing table:
6 Answers
6
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What is the purpose of setting a key in data.table?
I am using data.table and there are many functions which require me to set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
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How to reorder data.table columns (without copying)
I'd like to reorder columns in my data.table x , given a character vector of column names, neworder :
2 Answers
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Array to String PHP?
...e a DB is so you can accomplish work like this trivially. You don't need a table to store arrays, you need a table that you can represent as an array.
Example:
id | word
1 | Sports
2 | Festivals
3 | Classes
4 | Other
You would simply select the data from the table with SQL, rather than have ...
SQL query to find record with ID not in another table
I have two tables with binding primary key in database and I desire to find a disjoint set between them. For example,
6 Ans...