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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;
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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
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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 ...
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)...
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...
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...
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
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