mysql codeigniter - sql

How to do BETWEEN query with codeigniter's active record?

As a standalone method $this->db->between('field_name', 'min_value', 'max_value'), NO it does not exists. But you can use custom query strings in the where() method:
$this->db->where('age BETWEEN 18 AND 25', NULL);
Just search the CI forums, and you will find a couple of threads about it.

simple..
use this:
$this->db->where("sampledate between '$start' and '$end'",NULL,false);

Related

How to add allowDiskUse to mongooperation.find method in spring boot

The below query i want to add allowDiskUse true. I am able to add allowDiskUsage to aggregation query but not able to find a solution for find method
Query query = new Query().with(pageable).addCriteria(criteria).collation(collation);
mongoOperations.find(query, RuntimeApplication.class, RUNTIME_APP);
I want to know is that possible to add allowDiskUsage to find method or i need to change query to aggregation.
i just found in below query from internet. but i am not getting how to convert it into spring boot
db.collection.find(<match>).sort(<sort>).allowDiskUse()
What kind of spring-data version are you using? You should be able to add allowDiskUse to the Query object just like this:
val query = Query()
.with(Pageable.ofSize(1))
.addCriteria(Criteria())
.allowDiskUse(true)
And then afterwards use the query with find for instance with mongoTemplate.
Here is the documentation: https://javadoc.io/doc/org.springframework.data/spring-data-mongodb/latest/org/springframework/data/mongodb/core/query/Query.html

Math with datetime in SQL query in rails

So I have an table of phone_numbers in Rails 3.2, and I would like to be able to make a query such as the following:
PhoneNumber.where("last_called_at - #{Time.now} > call_spacing * 60")
where last_called_at is a datetime and call_spacing is an integer, representing the number of minutes between calls.
I have tried the above, I have also tried using
PhoneNumber.where("datediff(mi, last_called_at, #{Time.now}) > call_spacing")
If anyone could help me make this work, or even recommend a current, up-to-date rails SQL gem, I would be very grateful.
Edit: So the best way to make this work for me was to instead add a ready_at column to my database, and update that whenever either call_spacing or last_called_at was updated, using the before_save method. This is probably the most semantic way to approach this problem in rails.
You have to use quotes around #{Time.now}. To make your first query work you may use TIME_TO_SEC() function:
PhoneNumber.where("(TIME_TO_SEC('#{Time.now}') - TIME_TO_SEC(last_called_at)) > (call_spacing * 60)")
Here is my way to do this:
PhoneNumber.where("last_called_at > '#{Time.zone.now.utc - (call_spacing * 60)}'")
also take a look at this article to be aware of how to play with timezones:
http://danilenko.org/2012/7/6/rails_timezones/

IFNULL in Symfony2 Doctrine query builder

How is the IFNULL of SQL implemented in Symfony2 Doctrine Query Builder?
Let's say I have this query:
select * from ticket order by IFNULL(modified_date, '2000-01-01') DESC, created_date DESC
I have this DQL:
$this->qb->select("t, c.name")
->from("Ticket", "t");
$this->qb->orderBy("t.modifiedDate", "DESC");
$this->qb->addOrderBy("t.createdDate", "DESC");
Now how to add the IFNULL part?
Ok, done some research and found that there is no such implementation.
Googled a little more, and got that this kind of missing features can be added to Doctrine as own functions.
Found this extension on GitHub I think this will work. But wonder if ther would be any problems or conflicts with Doctrine versions...
This is the valid link with the DQL Extension
Edit with the solution explained:
Create the following directory under your project src path: /src/DoctrineExtensions/Query/Mysql
Put there the DQL Extension file (IfNull.php in this case)
Edit your src/config/packages/doctrine.yaml and insert this new lines:
doctrine:
...
orm:
...
dql:
numeric_functions:
IFNULL: App\DoctrineExtensions\Query\Mysql\IfNull
In your entity repository you can call this function like this:
$qb = $this->createQueryBuilder('tl')
->andWhere('IFNULL(tl.app,0) = 1');
Depending on your usecase you may be able to use the builtin "COALESCE" expression instead of installing the "IFNULL" extension.
The usage then is basically the same as with the IFNULL expression.
Just replace IFNULL with COALESCE in the example in https://stackoverflow.com/a/68827681/1707003.
Note: COALESCE might behave slightly different than IFNULL depending on your database. https://stackoverflow.com/a/18528590/1707003 contains some great explanations.
List of builtin case-expressions: https://www.doctrine-project.org/projects/doctrine-orm/en/2.13/reference/dql-doctrine-query-language.html#case-expressions

"Searching" a string on a MongoDB DB with MongoMapper

I'm making a webapp where I'm using MongoMapper and Sinatra. I wonder how could I implement a search feature against a DB's collection. I though something like SQL's:
SELECT * FROM posts WHERE match(title) against ("String to search");
How could I achieve this with MongoMapper? Thanks!
ok this is from my project and does work:
Post.where(:title => Regexp.new(/^string/i)) # Limit output with: .limit(10)
Maybe it's the Regexp?
You query for documents that match a case sensitive rooted regular expression:
Post.where(:title => /^stringtosearch/).first
MongoDB does not support full text search so this is the best you can do at the moment.

How to turn on REGEXP in SQLite3 and Rails 3.1?

I have the following statement in Rails 3 using an SQLite3 database:
word = 'Hello'
word_entry = Word.where("name REGEXP :word", {:word => "[[:<:]]#{word}[[:>:]]"})
However, when running this under SQLite3, I keep getting:
SQLite3::SQLException: no such function: REGEXP
I read in the SQLite3 documentation that it does indeed support the REGEXP function.
In my gemfile, I have the line
gem 'sqlite3'
And my database config file looks like this:
development:
adapter: sqlite3
database: db/development.sqlite3
pool: 5
timeout: 5000
Any ideas what's going on?
RESOLUTION:
I ended up finding this solution. Unfortunately, it doesn't work for Rails 3.
So to use regular expressions I ended up switching to MYSQL instead of SQLite3.
I ran into the same issue. I took the code used in the resolution, ported it to work with Rails 3+ and made a gem for easier use. I hope this helps.
https://github.com/sei-mi/sqlite3_ar_regexp
From the fine manual:
The REGEXP operator is a special syntax for the regexp() user function. No regexp() user function is defined by default and so use of the REGEXP operator will normally result in an error message. If a application-defined SQL function named "regexp" is added at run-time, that function will be called in order to implement the REGEXP operator.
So the grammar supports REGEXP but the default SQLite library does not provide an implementation for it. You'll have to hook up your own implementation through some C wrangling if you want or need such a thing.
Presumably the rationale is that the SQLite people want to keep SQLite as small and tight as possible but including a whole regular expression library would add weight that most people don't want. Also, they would have to choose a regular expression library and include it with the SQLite source or they'd have to put up with the vagaries of everyone's regular expression support in libc. I'm not one of the SQLite developers so this is pure speculation.
I'm guessing that you'll probably have to make do with LIKE and GLOB. Using LIKE will provide a more portable solution.
You may be intested in the sqlite3-pcre package, which implements REGEXP for SQLite.
See this comment on a similar issue.
I had a similar question, and found a Gem named wherex that is well documented and worked out of the box.
Your expression from above
Word.where("name REGEXP :word", {:word => "[[:<:]]#{word}[[:>:]]"})
would there be
Word.where(:name => Regexp.new("[[:<:]]#{word}[[:>:]]"))
Works like a charm for me :-)
From source of sqlite3_ar_regexp project, I extract this:
db = SQLite3::Database.open( database_name )
db.create_function('regexp', 2) do |func, pattern, expression|
func.result = expression.to_s.match(
Regexp.new(pattern.to_s, Regexp::IGNORECASE)) ? 1 : 0
end
From source of sqlite3_ar_regexp project, I extract this:
db = ActiveRecord::Base.connection.raw_connection
db.create_function('regexp', 2) do |func, pattern, expression|
func.result = expression.to_s.match(
Regexp.new(pattern.to_s, Regexp::IGNORECASE)) ? 1 : 0
end
Improved upon a previous answer with ActiveRecord::Base.connection.raw_connection so that db name isn't needed