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Undo scaffolding in Rails
...e db:rollback before you destroy your scaffold. This will destroy/drop the table if there is no other migration except the scaffold's migration before it.
– Yakob Ubaidi
May 8 '14 at 11:06
...
The cast to value type 'Int32' failed because the materialized value is null
...eady value. I think, that the error above is occured because CreditHistory table is empty. I have one record in User table and 0 records in CreditHistory table and error is occured. When I use DefaultIfEmpty(0).Sum() it works fine, but with ?? 0 it throws error. My another question is what is best...
How to iterate over array of objects in Handlebars?
...t;script id="small-template" type="text/x-handlebars-template">
<table>
<thead>
<th>Username</th>
<th>email</th>
</thead>
<tbody>
{{#data}}
<tr>
...
Storing Data in MySQL as JSON
... for directly in MySQL queries, but used when viewing forms (either from a table view or directly via a link). It's probably not ideal but it certainly makes it a lot quicker to implement and removes the need for an exorbitant amount of tables or table columns.
– Nick Bedford
...
How to escape apostrophe (') in MySql?
...y be written as “''”.
(Also, you linked to the MySQL 5.0 version of Table 8.1. Special Character Escape Sequences, and the current version is 5.6 — but the current Table 8.1. Special Character Escape Sequences looks pretty similar.)
I think the Postgres note on the backslash_quote (string)...
What integer hash function are good that accepts an integer hash key?
...hich is not uncommon), their hashes will be too. This is a problem in hash tables - you can end up with only 1/2 or 1/4 of the buckets being used.
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postgresql return 0 if returned value is null
...al question).
There are two distinct "problems" here, the first is if a table or subquery has no rows, the second is if there are NULL values in the query.
For all versions I've tested, postgres and mysql will ignore all NULL values when averaging, and it will return NULL if there is nothing to ...
How to express a NOT IN query with ActiveRecord/Rails?
...
Using Arel:
topics=Topic.arel_table
Topic.where(topics[:forum_id].not_in(@forum_ids))
or, if preferred:
topics=Topic.arel_table
Topic.where(topics[:forum_id].in(@forum_ids).not)
and since rails 4 on:
topics=Topic.arel_table
Topic.where.not(topics[:f...
Capitalize first letter. MySQL
...f you want to Uppercase the First Letter of EVERY word in the strings of a table column?
eg: "Abbeville High School"
I hadn't found an answer to this in Stackoverflow. I had to cobble together a few answers I found in Google to provide a solid solution to the above example. Its not a native functi...
Imitating a blink tag with CSS3 animations
... +animation(blink 1s 0s reverse infinite)
+transform(translateZ(0))
.table
display: table
height: 5em
width: 100%
vertical-align: middle
.cell
display: table-cell
width: 100%
height: 100%
vertical-align: middle
http://codepen.io/anon/pen/kaGxC (sass with bourbon)
...