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Automatically deleting related rows in Laravel (Eloquent ORM)
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You can actually set this up in your migrations:
$table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
Source: http://laravel.com/docs/5.1/migrations#foreign-key-constraints
You may also specify the desired action for the "on delete...
Set a DateTime database field to “Now”
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In SQL you need to use GETDATE():
UPDATE table SET date = GETDATE();
There is no NOW() function.
To answer your question:
In a large table, since the function is evaluated for each row, you will end up getting different values for the updated field.
So, if yo...
Postgres: How to do Composite keys?
... error, and omit the redundant CONSTRAINT (already implied), too:
CREATE TABLE tags
(
question_id INTEGER NOT NULL,
tag_id SERIAL NOT NULL,
tag1 VARCHAR(20),
tag2 VARCHAR(20),
tag3 VARCHAR(20),
PRIMARY ...
How can I access the MySQL command line with XAMPP for Windows?
... .\mysql -u root (use this in powershell ".\" means look for executable or binary in present working directory)
– Timothy L.J. Stewart
Jan 5 '17 at 20:39
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Storing Images in PostgreSQL
...ommend:
use blob (Binary Large OBject): for original image store, at your table. See Ivan's answer (no problem with backing up blobs!), PostgreSQL additional supplied modules, How-tos etc.
use a separate database with DBlink: for original image store, at another (unified/specialized) database. I...
ActiveRecord OR query
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Use ARel
t = Post.arel_table
results = Post.where(
t[:author].eq("Someone").
or(t[:title].matches("%something%"))
)
The resulting SQL:
ree-1.8.7-2010.02 > puts Post.where(t[:author].eq("Someone").or(t[:title].matches("%something%"))).to_...
Creating a jQuery object from a big HTML-string
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You can try something like below
$($.parseHTML(<<table html string variable here>>)).find("td:contains('<<some text to find>>')").first().prev().text();
share
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Oracle SQL Developer multiple table views
In Oracle SQL Developer , one can list the data in a table using the Data tab when viewing a table. there where can add, delete, edit or just viewing records of table currently viewd
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How do I clone a Django model instance object and save it to the database?
...tion checking and depending on if they pass, i.e. the object is in another table that you are checking, you can set the new_instance.id = original_instance.id and save :) Thanks!
– radtek
Sep 25 '14 at 21:43
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Are PostgreSQL column names case-sensitive?
I have a db table say, persons in Postgres handed down by another team that has a column name say, "first_Name" . Now am trying to use PG commander to query this table on this column-name.
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