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Populating a database in a Laravel migration file
... just learning Laravel, and have a working migration file creating a users table. I am trying to populate a user record as part of the migration:
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How to add 'ON DELETE CASCADE' in ALTER TABLE statement
I have a foreign key constraint in my table, I want to add ON DELETE CASCADE to it.
9 Answers
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How to find duplicates in 2 columns not 1
I have a MySQL database table with two columns that interest me. Individually they can each have duplicates, but they should never have a duplicate of BOTH of them having the same value.
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How can I add a column that doesn't allow nulls in a Postgresql database?
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You have to set a default value.
ALTER TABLE mytable ADD COLUMN mycolumn character varying(50) NOT NULL DEFAULT 'foo';
... some work (set real values as you want)...
ALTER TABLE mytable ALTER COLUMN mycolumn DROP DEFAULT;
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Make a DIV fill an entire table cell
...nswered) and we have CSS3! Is there any way to get a div to fill an entire table cell's width and height using CSS?
26 Answ...
What are the uses for Cross Join?
...t
size,
color
from
sizes CROSS JOIN colors
Maybe you want a table that contains a row for every minute in the day, and you want to use it to verify that a procedure has executed each minute, so you might cross three tables:
select
hour,
minute
from
hours CROSS JOIN minute...
Quickly reading very large tables as dataframes
I have very large tables (30 million rows) that I would like to load as a dataframes in R. read.table() has a lot of convenient features, but it seems like there is a lot of logic in the implementation that would slow things down. In my case, I am assuming I know the types of the columns ahead o...
Difference between natural join and inner join
...INNER JOIN and NATURAL JOIN is the number of columns returned.
Consider:
TableA TableB
+------------+----------+ +--------------------+
|Column1 | Column2 | |Column1 | Column3 |
+-----------------------+ +--------------------+
| 1 ...
Is it possible to for SQL Output clause to return a column not being inserted?
...modifications to my database and I need to migrate the old data to the new tables. For that, I need to fill a table (ReportOptions) taking the data from the original table (Practice), and fill a second intermediate table (PracticeReportOption).
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MySQL: #126 - Incorrect key file for table
...is can be caused by a full ramdisk when doing things like altering a large table if you have a ramdisk configured. You can temporarily comment out the ramdisk line to allow such operations if you can't increase the size of it.
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