Class: Shiba::Index

Inherits:
Object
  • Object
show all
Defined in:
lib/shiba/index.rb

Class Method Summary collapse

Class Method Details

.parse(path) ⇒ Object

Given the path to the information_schema.statistics output, returns index statistics keyed by table name. Examples: Exploring the schema:

schema_stats = Index.parse(“./shiba/schema_stats.tsv”) schema_stats.keys

> :users, :posts, :comments

schema_stats

> :table_name=>“users”, :non_unique=>“0”, :column_name=>“id”, :cardinality=>“2”, :is_visible=>“YES”, :“expressionn”=>“NULLn”



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# File 'lib/shiba/index.rb', line 17

def self.parse(path)
  stats = IndexStats.new
  tables = {}
  records = read(path)
  headers = records.shift.map { |header| header.downcase }
  records.each do |r|
    h = Hash[headers.zip(r)]
    h["cardinality"] = h["cardinality"].to_i
    stats.add_index_column(h['table_name'], h['index_name'], h['column_name'], h['cardinality'], h['non_unique'] == "0")
  end
  stats
end