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Entity Attribute Value Database vs. strict Relational Model Ecommerce
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What if you had a single table with indexes for text values 1-n, then in C# (in ram) map what you want to what you need. It would still work like an EAV, but the "matches" would be domain models. Sort of like a serialization, but you could use SQL ...
Postgres: “ERROR: cached plan must not change result type”
...ement for execution.
Meanwhile, another script was modifying the database table, changing the data type of one of the columns being returned in the above SELECT statement.
I resolved this by restarting the application after the database table was modified. This reset the database connection, allow...
Why is vertical-align: middle not working on my span or div?
...ow: http://jsfiddle.net/m3ykdyds/200
/* CSS file */
.main {
display: table;
}
.inner {
border: 1px solid #000000;
display: table-cell;
vertical-align: middle;
}
/* HTML File */
<div class="main">
<div class="inner"> This </div>
</div>
...
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>
...
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 ...
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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How to express a NOT IN query with ActiveRecord/Rails?
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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...
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)...
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...
count(*) vs count(column-name) - which is more correct? [duplicate]
...hich values of column is not NULL, whereas COUNT(*) counts all rows of the table.
– PureSilence
Oct 3 '19 at 7:49
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