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Why do we need message brokers like RabbitMQ over a database like PostgreSQL?
...n it needs to be, eliminating the need for wasteful checks.
locking of the table -> again low performing: There is no table to lock :P
millions of rows of task -> again polling is low performing: As mentioned above, Rabbitmq will operate faster as it resides RAM, and provides flow control. If ...
MySQL - Using COUNT(*) in the WHERE clause
...similar to this:
SELECT column_name, aggregate_function(column_name)
FROM table_name
WHERE column_name operator value
GROUP BY column_name
HAVING aggregate_function(column_name) operator value;
share
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IDENTITY_INSERT is set to OFF - How to turn it ON?
... for linking files). I do not want to take identity_insert off the entire table, as the increment by one works great. In my insert to TBL_Content store procedure I have something like this
...
How big can a user agent string get?
...
My take on this:
Use a dedicated table to store only UserAgents (normalize it)
In your related tables, store an Foreign Key value to point back to the UserAgent auto-increment primary key field
Store the actual UserAgent string in a TEXT field and care not a...
JPA - Returning an auto generated id after persist()
... Its not working giving zero as a Return after persisting the data into table. either refresh is not working at this case .. What should i do for this. please suggest a way... Thank you
– Vikrant Kashyap
Jun 13 '16 at 6:57
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In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
... Not sure why this is the accepted answer... OP is using multi-table inheritance. This answer is only valid for abstract base classes.
– MrName
Mar 12 '18 at 21:39
1
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Infinite Recursion with Jackson JSON and Hibernate JPA issue
...r code like this (I skip the useless parts):
Business Object 1:
@Entity
@Table(name = "ta_trainee", uniqueConstraints = {@UniqueConstraint(columnNames = {"id"})})
public class Trainee extends BusinessObject {
@OneToMany(mappedBy = "trainee", fetch = FetchType.EAGER, cascade = CascadeType.ALL)...
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
...
Store select query's output in one array in postgres
...
SELECT array_agg(column_name::TEXT)
FROM information.schema.columns
WHERE table_name = 'aean'
The other is to use an array constructor:
SELECT ARRAY(
SELECT column_name
FROM information.schema.columns
WHERE table_name = 'aean')
I'm presuming this is for plpgsql. In that case you can assign i...
Entity Framework select distinct name
...inct Name:
Suppose if you are using Views in which you are using multiple tables and you want to apply distinct in that case first you have to store value in variable & then you can apply Distinct on that variable like this one....
public List<Item_Img_Sal_VIEW> GetItemDescription(int It...