Class: Randumb::Syntax
- Inherits:
-
Object
- Object
- Randumb::Syntax
- Defined in:
- lib/randumb/syntax.rb
Class Method Summary collapse
-
.random_order_clause(opts = {}) ⇒ Object
builds the order clause to be appended in where clause.
-
.random_weighted_order_clause(ranking_column, opts = {}) ⇒ Object
builds the order clause to be appended in where clause.
Class Method Details
.random_order_clause(opts = {}) ⇒ Object
builds the order clause to be appended in where clause
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# File 'lib/randumb/syntax.rb', line 6 def random_order_clause(opts={}) random_for(opts) end |
.random_weighted_order_clause(ranking_column, opts = {}) ⇒ Object
builds the order clause to be appended in where clause
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# File 'lib/randumb/syntax.rb', line 11 def random_weighted_order_clause(ranking_column, opts={}) connection = opts[:connection] if connection.adapter_name =~ /sqlite/i # computer multiplication is faster than division I was once taught...so translate here max_int = 9223372036854775807.0 multiplier = 1.0 / max_int "(#{ranking_column} * ABS(#{random_for(opts)} * #{multiplier}) ) DESC" else "(#{ranking_column} * #{random_for(opts)}) DESC" end end |