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How to find gaps in sequential numbering in mysql?
...t column, and there are no duplicate values, but there are missing values. For example, running this query:
11 Answers
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MySQL INNER JOIN select only one row from second table
I have a users table and a payments table, for each user, those of which have payments, may have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL sta...
How can I get a channel ID from YouTube?
...ing to retrive the data from my channel using the YouTube Data API V3 .
For that I need my channel ID.
I've tried to find my channel ID from my YouTube account, and I failed in every single way.
If anyone have a single tip for me, I would be incredible glad.
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Many-to-many relationship with the same model in rails?
...to ask yourself the following questions:
Do I want to store additional information with the association? (Additional fields in the join table.)
Do the associations need to be implicitly bi-directional?
(If post A is connected to post B, then post B is also connected to post A.)
That leaves four ...
Overriding id on create in ActiveRecord
...of the database on every call, you just store your data in yml files. The foreign keys in the database reference the in-memory ids in the yml.
ActiveHash is great for picklists and small tables that change infrequently and only change by developers. So when going from ActiveHash to ActiveRecord, ...
JavaScript - onClick to get the ID of the clicked button
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I just wanted to note, for anyone getting a null reference exception using JQuery's event.target.id (for me, both Firefox and IE were throwing it), this is a great solution that works in all three major browsers.
– X3074861X
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Schema for a multilanguage database
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What do you think about having a related translation table for each translatable table?
CREATE TABLE T_PRODUCT (pr_id int, PRICE NUMBER(18, 2))
CREATE TABLE T_PRODUCT_tr (pr_id INT FK, languagecode varchar, pr_name text, pr_descr text)
This way if you have multiple translatable col...
Using LIMIT within GROUP BY to get N results per group?
..._in_set, you could then use this query that returns only the first 5 years for every id:
SELECT
yourtable.*
FROM
yourtable INNER JOIN (
SELECT
id,
GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM
yourtable
GROUP BY id) group_max
ON yourtable.id = group_max...
How to drop SQL default constraint without knowing its name?
...osoft SQL Server, I know the query to check if a default constraint exists for a column and drop a default constraint is:
1...
Does MongoDB's $in clause guarantee order
...sults
{ "$sort": { "weight": 1 } }
])
So that would be the expanded form. What basically happens here is that just as the array of values is passed to $in you also construct a "nested" $cond statement to test the values and assign an appropriate weight. As that "weight" value reflects the ord...