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When should you not use virtual destructors?
...mean every allocated object increases in memory cost by a virtual function table pointer.
So if your program involves allocating a very large number of some object, it would be worth avoiding all virtual functions in order to save the additional 32 bits per object.
In all other cases, you will sav...
Downloading MySQL dump from command line
...mp -u [uname] -p --all-databases > all_db_backup.sql
If it's specific tables within a DB, then:
$ mysqldump -u [uname] -p db_name table1 table2 > table_backup.sql
You can even go as far as auto-compressing the output using gzip (if your DB is very big):
$ mysqldump -u [uname] -p db...
Laravel Eloquent: How to get only certain columns from joined tables
I have got 2 joined tables in Eloquent namely themes and users.
15 Answers
15
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How do I (or can I) SELECT DISTINCT on multiple columns?
I need to retrieve all rows from a table where 2 columns combined are all different. So I want all the sales that do not have any other sales that happened on the same day for the same price. The sales that are unique based on day and price will get updated to an active status.
...
Difference between partition key, composite key and clustering key in Cassandra?
...neral concept to indicate one or more columns used to retrieve data from a Table.
The primary key may be SIMPLE and even declared inline:
create table stackoverflow_simple (
key text PRIMARY KEY,
data text
);
That means that it is made by a single column.
But the primary ke...
How do I set a background-color for the width of text, not the width of the entire element, using CS
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display:table is a better choice... to avoid the problem highlighted in the comments section in the next reply. display:inline will concatenate <h1> and <h2> to be in same line.... when they are originally in next lines.
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Render Partial View Using jQuery in ASP.NET MVC
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@Zapnologica - if you're reloading the entire table, you might need to reapply the plugin since the DOM elements it was originally connected to have been replaced. It might be better to connect it to a method that returns the data as JSON, datatables.net/examples/data_so...
Unable to update the EntitySet - because it has a DefiningQuery and no element exis
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Entity Set is mapped from Database view
A custom Database query
Database table doesn't have a primary key
After doing so, you may still need to update in the Entity Framework designer (or alternatively delete the entity and then add it) before you stop getting the error.
...
How do you rename a MongoDB database?
...pyDatabase('testing','movies');
So in this context all the collections (tables) of testing will be copied to movies database.
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Why do I get a “Null value was assigned to a property of primitive type setter of” error message whe
...he solution is replace primitive type with primitive wrapper class in your tableName.java file.
Such as:
@Column(nullable=true, name="client_os_id")
private Integer client_os_id;
public int getClient_os_id() {
return client_os_id;
}
public void setClient_os_id(int clientOsId) {
client_os_...