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SQLite UPSERT / UPDATE OR INSERT
... there are two ways to accomplish this, depending on the structure of your table and if you have foreign keys restrictions activated to maintain integrity. I'd like to share this in a clean format to save some time to the people that may be in my situation.
Option 1: You can afford deleting the row...
How do I automatically update a timestamp in PostgreSQL
...
To populate the column during insert, use a DEFAULT value:
CREATE TABLE users (
id serial not null,
firstname varchar(100),
middlename varchar(100),
lastname varchar(100),
email varchar(200),
timestamp timestamp default current_timestamp
)
Note that the value for that column c...
How can I avoid Java code in JSP files, using JSP 2?
...fway, all you get is a blank page.
Testability: scriptlets are not unit-testable.
Maintainability: per saldo more time is needed to maintain mingled/cluttered/duplicated code logic.
Sun Oracle itself also recommends in the JSP coding conventions to avoid use of scriptlets whenever the same functio...
Cost of len() function
... the most common implementation of the Python language. Here's a link to a table that provides the algorithmic complexity of many different functions in CPython:
TimeComplexity Python Wiki Page
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IDENTITY_INSERT is set to OFF - How to turn it ON?
... for linking files). I do not want to take identity_insert off the entire table, as the increment by one works great. In my insert to TBL_Content store procedure I have something like this
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What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
... take up different amounts of space and they have different ranges of acceptable values.
Here are the sizes and ranges of values for SQL Server, other RDBMSes have similar documentation:
MySQL
Postgres
Oracle (they just have a NUMBER datatype really)
DB2
Turns out they all use the same specific...
How does @synchronized lock/unlock in Objective-C?
...dn't feel like writing section directives in order build the DWARF3 unwind tables ;-)
– Louis Gerbarg
Aug 1 '09 at 1:33
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Avoid line break between html elements
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nobr is too unreliable, use tables
<table>
<tr>
<td> something </td>
<td> something </td>
</tr>
</table>
It all goes on the same line, everything is level with eachother,...
MongoDB and “joins” [duplicate]
...r hand will resolve relationships and return them as if they were a single table (you "join two tables into one").
You can read more about DBRef here:
http://docs.mongodb.org/manual/applications/database-references/
There are two possible solutions for resolving references. One is to do it manuall...
delete_all vs destroy_all?
I am looking for the best approach to delete records from a table. For instance, I have a user whose user ID is across many tables. I want to delete this user and every record that has his ID in all tables.
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