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module ActiveRecord::ConnectionAdapters::QueryCache
Attributes
query_cache[R]
query_cache_enabled[R]
Public Class Methods
# File activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb, line 17
def dirties_query_cache(base, *method_names)
method_names.each do |method_name|
base.class_eval <<-end_code, __FILE__, __LINE__ + 1
def #{method_name}(*)
ActiveRecord::Base.clear_query_caches_for_current_thread
super
end
end_code
end
end
# File activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb, line 52
def initialize(*)
super
@query_cache = Hash.new { |h, sql| h[sql] = {} }
@query_cache_enabled = false
end
Calls superclass method
Public Instance Methods
# File activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb, line 59
def cache
old, @query_cache_enabled = @query_cache_enabled, true
yield
ensure
@query_cache_enabled = old
clear_query_cache unless @query_cache_enabled
end
Enable the query cache within the block.
# File activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb, line 90
def clear_query_cache
@lock.synchronize do
@query_cache.clear
end
end
Clears the query cache.
One reason you may wish to call this method explicitly is between queries that ask the database to randomize results. Otherwise the cache would see the same SQL query and repeatedly return the same result each time, silently undermining the randomness you were expecting.
# File activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb, line 71
def disable_query_cache!
@query_cache_enabled = false
clear_query_cache
end
# File activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb, line 67
def enable_query_cache!
@query_cache_enabled = true
end
# File activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb, line 96
def select_all(arel, name = nil, binds = [], preparable: nil)
if @query_cache_enabled && !locked?(arel)
arel = arel_from_relation(arel)
sql, binds, preparable = to_sql_and_binds(arel, binds, preparable)
cache_sql(sql, name, binds) { super(sql, name, binds, preparable: preparable) }
else
super
end
end
Calls superclass method
# File activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb, line 77
def uncached
old, @query_cache_enabled = @query_cache_enabled, false
yield
ensure
@query_cache_enabled = old
end
Disable the query cache within the block.
© 2004–2020 David Heinemeier Hansson
Licensed under the MIT License.