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Margin while printing html page
...tyle will not adjust the margin in the printer driver that defines the printable area of the printer, or margin controlled by the browser (may be adjustable in print preview on some browsers)... It will just set margin on the document inside the printable area.
You should also be aware that IE7++ ...
Ways to save enums in database
...g.
But if you wanted to really do that, i would create a Suits dimension table:
| Suit | SuitID | Rank | Color |
|------------|--------------|---------------|--------|
| Unknown | 4 | 0 | NULL |
| Heart | 1 | 1 | Red ...
Change a column type from Date to DateTime during ROR migration
...
First in your terminal:
rails g migration change_date_format_in_my_table
Then in your migration file:
For Rails >= 3.2:
class ChangeDateFormatInMyTable < ActiveRecord::Migration
def up
change_column :my_table, :my_column, :datetime
end
def down
change_column :my_tabl...
ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired
Why am I getting this database error when I update a table?
14 Answers
14
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The multi-part identifier could not be bound
...
FROM (a, b) LEFT JOIN dkcd ON …
WHERE …
that is, the combination of tables a and b is joined with the table dkcd. In fact, what's happening is
SELECT
…
FROM a, (b LEFT JOIN dkcd ON …)
WHERE …
that is, as you may already have understood, dkcd is joined specifically against b and onl...
T-SQL: Deleting all duplicate rows but keeping one [duplicate]
I have a table with a very large amount of rows. Duplicates are not allowed but due to a problem with how the rows were created I know there are some duplicates in this table.
I need to eliminate the extra rows from the perspective of the key columns. Some other columns may have slightly different...
Parse JSON in TSQL
...le Talk website that outlines how to take a JSon string and output it into tables and columns that can be queried. This is for SQL Server 2016: https://www.simple-talk.com/sql/learn-sql-server/json-support-in-sql-server-2016/
– codeaf
Jul 28 '16 at 18:10
...
First-time database design: am I overengineering? [closed]
...ds. Unless you are talking about well over a million records in your main tables you seem to be on track to having a sufficiently mainstream design that performance will not be an issue on reasonable hardware.
That said, and this relates to your question 3, with the start you have you probably s...
Rails: Using greater than/less than with a where statement
...non discrete values or columns where you can't use the + 1 strategy.
Arel table
If you want to get fancy you can make use of the Arel::Table.
User.where(User.arel_table[:id].gt(200))
will generate the SQL
"SELECT `users`.* FROM `users` WHERE (`users`.`id` > 200)"
The specifics are as foll...
Check if value exists in Postgres array
...
how can I search for a column from another table to have a value in the array? e.g. select * from beers where style_id in (select preferences from users where id=1) limit 1; style_id is an integer data type; preferences is integer[] I get this error ERROR: operato...