QueryablePStore

QueryablePStore is a quick and easy way to query a PStore file. It's syntax is inspired by ActiveRecord, but is more simplified. Of note, appending .results is required to actually execute the query and return the results.

Examples:

Assuming a testing.pstore file that has the following hash saved:

{
  1: { name: "John Doe", age: 28, weight: 150.0, email: "[email protected]" },
  2: { name: "Alpha Bet", age: 18, weight: 170.0, email: "[email protected]" },
  3: { name: "Charlie Dog", age: 46, weight: 182.9, email: "[email protected]" },
  4: { name: "Eddy Foobar", age: 72, weight: 200.0, email: "[email protected]" },
  5: { name: "George Hallo", age: 50, weight: 246.0, email: "[email protected]" },
}

• All users older than 30:

q = QueryablePStore.new("testing.pstore")
q.age_gt(30).results

• All Users younger than 60 with a weight greater than 100:

q = QueryablePStore.new("testing.pstore")
q.age_lt(60).weight_gt(100.0).results

The attributes_lambda function recieves the entire record wrapped in an OpenStruct, so both [] and dot-notation access methods are supported.

• All Users with an email ending with example.com:

q = QueryablePStore.new("testing.pstore")
q.attributes_lambda { |row| row.email.end_with?("example.com") }.results
# OR
q.attributes_lambda { |row| row[:email].end_with?("example.com") }.results

CSV Import

The library also supports importing a CSV that is already written to disk. It will then create a PStore at the location #{filename}.pstore and return an instance of a QueryablePStore loaded for you to use.

q = QueryablePStore.import_csv("test.csv")
q.name_eq("John Doe").results

It will normalize all headers by downcasing all alpha characters ([a-zA-Z]) and replacing any other characters with _.

Example:

"Hello World" => :hello_world
"$/yr" => :__yr
"Test-Header" => :test_header

Additionally, you can let QueryablePStore know how to convert integer and float fields so that gt and lt queries can use numbers rather than strings for comparisons.

q = QueryablePStore.import_csv("test.csv", convert: [age: :integer])
q.age_gt(20).results