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Using IQueryable with Linq
...tabase, with many ORM systems, you have the option of fetching data from a table in two ways, one which returns IEnumerable<T>, and one which returns an IQueryable<T>. Say, for example, you have a Products table, and you want to get all of the products whose cost is >$25.
If you do:...
Is it possible to refresh a single UITableViewCell in a UITableView?
I have a custom UITableView using UITableViewCell s.
Each UITableViewCell has 2 buttons. Clicking these buttons will change an image in a UIImageView within the cell.
...
How to include “zero” / “0” results in COUNT aggregate?
...u want an outer join for this (and you need to use person as the "driving" table)
SELECT person.person_id, COUNT(appointment.person_id) AS "number_of_appointments"
FROM person
LEFT JOIN appointment ON person.person_id = appointment.person_id
GROUP BY person.person_id;
The reason why this is wo...
MySQL “incorrect string value” error when save unicode string in Django
...developer here)
To solve this you need to:
Change your MySQL database, table and columns to use the utf8mb4 character set (only available from MySQL 5.5 onwards)
Specify the charset in your Django settings file as below:
settings.py
DATABASES = {
'default': {
'ENGINE':'django.db....
What good are SQL Server schemas?
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Schemas logically group tables, procedures, views together. All employee-related objects in the employee schema, etc.
You can also give permissions to just one schema, so that users can only see the schema they have access to and nothing else.
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How do I flush the PRINT buffer in TSQL?
... on PRINT or RAISERROR and just load your "print" statements into a ##Temp table in TempDB or a permanent table in your database which will give you visibility to the data immediately via a SELECT statement from another window. This works the best for me. Using a permanent table then also serves a...
MySQL DISTINCT on a GROUP_CONCAT()
I am doing SELECT GROUP_CONCAT(categories SEPARATOR ' ') FROM table . Sample data below:
6 Answers
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2 column div layout: right column with fixed width, left fluid
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Simplest and most flexible solution so far it to use table display:
HTML, left div comes first, right div comes second ... we read and write left to right, so it won't make any sense to place the divs right to left
<div class="container">
<div class="left">
...
PostgreSQL LIKE query performance variations
...large variation in response times regarding LIKE queries to a particular table in my database. Sometimes I will get results within 200-400 ms (very acceptable) but other times it might take as much as 30 seconds to return results.
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SQL Switch/Case in 'where' clause
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I'd say this is an indicator of a flawed table structure. Perhaps the different location types should be separated in different tables, enabling you to do much richer querying and also avoid having superfluous columns around.
If you're unable to change the structur...