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How to set a default value for a datetime column to record creation time in a migration?
Consider the table creation script below:
7 Answers
7
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schema builder laravel migrations unique on two columns
...array as the first param to create a unique key across multiple columns.
$table->unique(array('mytext', 'user_id'));
or (a little neater)
$table->unique(['mytext', 'user_id']);
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im...
Auto increment in phpmyadmin
... column. I guess the phpMyAdmin version is 3.5.5 but not sure.
Click on Table > Structure tab > Under Action
Click Primary (set as primary),
click on Change on the pop-up window, scroll left and check A_I. Also make sure you have selected None for Default
...
In MySQL what does “Overhead” mean, what is bad about it, and how to fix it?
...uld only worry if this gets really high.
You can compare 'Optimizing the table' with the defragmenting of your hard drive.
I quote:
Every database will, over time,
require some form of maintenance to
keep it at an optimal performance
level. Purging deleted rows,
resequencing, compre...
Entity Framework. Delete all rows in table
How I can quickly remove all rows in table using Entity Framework?
21 Answers
21
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Nullable Foreign Key bad practice?
Let's say you have a table Orders with a foreign key to a Customer Id. Now, suppose you want to add an Order without a Customer Id, (whether that should be possible is another question) you would have to make the foreign key NULL... Is that bad practice or would you rather work with a link table bet...
When should I use cross apply over inner join?
...readable and probably less efficient.
Update:
Just checked.
master is a table of about 20,000,000 records with a PRIMARY KEY on id.
This query:
WITH q AS
(
SELECT *, ROW_NUMBER() OVER (ORDER BY id) AS rn
FROM master
),
t AS
(
SELEC...
How can I copy data from one column to another in the same table?
Is it possible to copy data from column A to column B for all records in a table in SQL?
3 Answers
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List columns with indexes in PostgreSQL
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Create some test data...
create table test (a int, b int, c int, constraint pk_test primary key(a, b));
create table test2 (a int, b int, c int, constraint uk_test2 unique (b, c));
create table test3 (a int, b int, c int, constraint uk_test3b unique (b), co...
Permission denied for relation
...
GRANT on the database is not what you need. Grant on the tables directly.
Granting privileges on the database mostly is used to grant or revoke connect privileges. This allows you to specify who may do stuff in the database if they have sufficient other permissions.
You want ins...