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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 16
def dirties_query_cache(base, *method_names)
method_names.each do |method_name|
base.class_eval <<-end_code, __FILE__, __LINE__ + 1
def #{method_name}(*)
clear_query_cache if @query_cache_enabled
super
end
end_code
end
end
# File activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb, line 51
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 58
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 89
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 70
def disable_query_cache!
@query_cache_enabled = false
clear_query_cache
end
# File activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb, line 66
def enable_query_cache!
@query_cache_enabled = true
end
# File activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb, line 95
def select_all(arel, name = nil, binds = [], preparable: nil)
if @query_cache_enabled && !locked?(arel)
arel = arel_from_relation(arel)
sql, binds = to_sql_and_binds(arel, binds)
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 76
def uncached
old, @query_cache_enabled = @query_cache_enabled, false
yield
ensure
@query_cache_enabled = old
end
Disable the query cache within the block.
© 2004–2018 David Heinemeier Hansson
Licensed under the MIT License.