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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...
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.
...
Why are Oracle table/column/index names limited to 30 characters?
...haracters long. Allowing every line of code that goes something like
l_table_name VARCHAR2(30);
BEGIN
SELECT table_name
INTO l_table_name
FROM dba_tables
WHERE ...
to suddenly break because the DBA 15 years ago used VARCHAR2(30) rather than DBA_TABLES.TABLE_NAME%TYPE in the script...
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 “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?
...
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.
...
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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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.
...
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...
UITableView set to static cells. Is it possible to hide some of the cells programmatically?
UITableView set to static cells.
22 Answers
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