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Laravel migration: unique key is too long, even if specified
I am trying to migrate a users table in Laravel. When I run my migration I get this error:
38 Answers
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Add new column with foreign key constraint in one command
...to add the column and the foreign key constraint using two separate ALTER TABLE commands:
12 Answers
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What are the differences between a clustered and a non-clustered index?
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Clustered Index
Only one per table
Faster to read than non clustered as data is physically stored in index order
Non Clustered Index
Can be used many times per table
Quicker for insert and update operations than a clustered index
Both types of inde...
How to create id with AUTO_INCREMENT on Oracle?
...acle 11g. However, you can model it easily with a sequence and a trigger:
Table definition:
CREATE TABLE departments (
ID NUMBER(10) NOT NULL,
DESCRIPTION VARCHAR2(50) NOT NULL);
ALTER TABLE departments ADD (
CONSTRAINT dept_pk PRIMARY KEY (ID));
CREATE SEQUENCE dept_seq STA...
Best way to center a on a page vertically and horizontally? [duplicate]
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@FlashThunder you suggest tables for non-table data, aren't you?
– Vladimir Starkov
Jan 10 '15 at 3:17
1
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How do I drop a function if it already exists?
...'TF')
)
DROP FUNCTION function_name
GO
If you want to avoid the sys* tables, you could instead do (from here in example A):
IF object_id(N'function_name', N'FN') IS NOT NULL
DROP FUNCTION function_name
GO
The main thing to catch is what type of function you are trying to delete (denoted...
Ordering by specific field value first
I have a table with 3 columns:
8 Answers
8
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How do I force Postgres to use a particular index?
...meters. See:
Examining index usage
enable_ parameters
These are not suitable for ongoing production use. If you have issues with query plan choice, you should see the documentation for tracking down query performance issues. Don't just set enable_ params and walk away.
Unless you have a very go...
How can I query a value in SQL Server XML column
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select
Roles
from
MyTable
where
Roles.value('(/root/role)[1]', 'varchar(max)') like 'StringToSearchFor'
These pages will show you more about how to query XML in T-SQL:
Querying XML fields using t-sql
Flattening XML Data in SQL Server
EDIT
Aft...
Removing a model in rails (reverse of “rails g model Title…”)
...oy' on that model, it will delete the migration file, but not the database table. So before run
bundle exec rake db:rollback
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