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Why are Oracle table/column/index names limited to 30 characters?
...haracters long. Allowing every line of code that goes something like
l_table_name VARCHAR2(30);
BEGIN
SELECT table_name
INTO l_table_name
FROM dba_tables
WHERE ...
to suddenly break because the DBA 15 years ago used VARCHAR2(30) rather than DBA_TABLES.TABLE_NAME%TYPE in the script...
Disable Laravel's Eloquent timestamps
... we don't want to add the updated_at / created_at fields to all of our tables as we have a logging class that does all this in more depth for us already.
...
How to scroll to the bottom of a UITableView on the iPhone before the view appears
I have a UITableView that is populated with cells of a variable height. I would like the table to scroll to the bottom when the view is pushed into view.
...
List all the files that ever existed in a Git repository
...$ git ff create
A database/migrations/2014_10_12_000000_create_users_table.php
A database/migrations/2014_10_12_100000_create_password_resets_table.php
A database/migrations/2015_05_11_200932_create_boletin_table.php
A database/migrations/2015_05_15_133500_create_usuarios_tab...
Foreign Key to non-primary key
I have a table which holds data, and one of those rows needs to exist in another table. So, I want a foreign key to maintain referential integrity.
...
Oracle: how to UPSERT (update or insert into a table?)
The UPSERT operation either updates or inserts a row in a table, depending if the table already has a row that matches the data:
...
Efficiently convert rows to columns in sql server
...Code, LastName, AccountNumber
from
(
select value, columnname
from yourtable
) d
pivot
(
max(value)
for columnname in (Firstname, Amount, PostalCode, LastName, AccountNumber)
) piv;
See Demo.
Pivot with unknown number of columnnames
If you have an unknown number of columnnames that you w...
sqlite alter table add MULTIPLE columns in a single statement
Is it possible to alter table add MULTIPLE columns in a single statement in sqlite?
The following would not work.
4 Answers...
MySQL ON vs USING?
...fferences are noteworthy:
ON is the more general of the two. One can join tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a column of the exac...
How do I find which transaction is causing a “Waiting for table metadata lock” state?
I am trying to perform some DDL on a table and SHOW PROCESSLIST results in a " Waiting for table metadata lock " message.
...