# File lib/active_record/connection_adapters/schema_cache.rb, line 298 def primary_keys(pool, table_name) @primary_keys.fetch(table_name) do pool.with_connection do |connection| if data_source_exists?(pool, table_name) @primary_keys[deep_deduplicate(table_name)] = deep_deduplicate(connection.primary_key(table_name)) end end end end
class ActiveRecord::ConnectionAdapters::SchemaCache
Active Record Connection Adapters Schema
Cache¶ ↑
Private Class Methods
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# File lib/active_record/connection_adapters/schema_cache.rb, line 244 def self.read(filename, &block) if File.extname(filename) == ".gz" Zlib::GzipReader.open(filename) { |gz| yield gz.read } else yield File.read(filename) end end
Public Instance Methods
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# File lib/active_record/connection_adapters/schema_cache.rb, line 326 def add(pool, table_name) pool.with_connection do if data_source_exists?(pool, table_name) primary_keys(pool, table_name) columns(pool, table_name) columns_hash(pool, table_name) indexes(pool, table_name) end end end
Add internal cache for table with table_name
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# File lib/active_record/connection_adapters/schema_cache.rb, line 294 def cached?(table_name) @columns.key?(table_name) end
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# File lib/active_record/connection_adapters/schema_cache.rb, line 388 def clear_data_source_cache!(_connection, name) @columns.delete name @columns_hash.delete name @primary_keys.delete name @data_sources.delete name @indexes.delete name end
Clear out internal caches for the data source name
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# File lib/active_record/connection_adapters/schema_cache.rb, line 338 def columns(pool, table_name) if ignored_table?(table_name) raise ActiveRecord::StatementInvalid.new("Table '#{table_name}' doesn't exist", connection_pool: pool) end @columns.fetch(table_name) do pool.with_connection do |connection| @columns[deep_deduplicate(table_name)] = deep_deduplicate(connection.columns(table_name)) end end end
Get the columns for a table
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# File lib/active_record/connection_adapters/schema_cache.rb, line 352 def columns_hash(pool, table_name) @columns_hash.fetch(table_name) do @columns_hash[deep_deduplicate(table_name)] = columns(pool, table_name).index_by(&:name).freeze end end
Get the columns for a table as a hash, key is the column name value is the column object.
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# File lib/active_record/connection_adapters/schema_cache.rb, line 359 def columns_hash?(_pool, table_name) @columns_hash.key?(table_name) end
Checks whether the columns hash is already cached for a table.
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# File lib/active_record/connection_adapters/schema_cache.rb, line 309 def data_source_exists?(pool, name) return if ignored_table?(name) if @data_sources.empty? tables_to_cache(pool).each do |source| @data_sources[source] = true end end return @data_sources[name] if @data_sources.key? name @data_sources[deep_deduplicate(name)] = pool.with_connection do |connection| connection.data_source_exists?(name) end end
A cached lookup for table existence.
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# File lib/active_record/connection_adapters/schema_cache.rb, line 406 def dump_to(filename) open(filename) { |f| if filename.include?(".dump") f.write(Marshal.dump(self)) else f.write(YAML.dump(self)) end } end
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# File lib/active_record/connection_adapters/schema_cache.rb, line 363 def indexes(pool, table_name) @indexes.fetch(table_name) do pool.with_connection do |connection| if data_source_exists?(pool, table_name) @indexes[deep_deduplicate(table_name)] = deep_deduplicate(connection.indexes(table_name)) else [] end end end end
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# File lib/active_record/connection_adapters/schema_cache.rb, line 379 def schema_version @version end
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# File lib/active_record/connection_adapters/schema_cache.rb, line 383 def size [@columns, @columns_hash, @primary_keys, @data_sources].sum(&:size) end
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# File lib/active_record/connection_adapters/schema_cache.rb, line 375 def version(pool) @version ||= pool.with_connection(&:schema_version) end
Private Instance Methods
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# File lib/active_record/connection_adapters/schema_cache.rb, line 448 def deep_deduplicate(value) case value when Hash value.transform_keys { |k| deep_deduplicate(k) }.transform_values { |v| deep_deduplicate(v) } when Array value.map { |i| deep_deduplicate(i) } when String, Deduplicable -value else value end end
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# File lib/active_record/connection_adapters/schema_cache.rb, line 440 def derive_columns_hash_and_deduplicate_values @columns = deep_deduplicate(@columns) @columns_hash = @columns.transform_values { |columns| columns.index_by(&:name) } @primary_keys = deep_deduplicate(@primary_keys) @data_sources = deep_deduplicate(@data_sources) @indexes = deep_deduplicate(@indexes) end
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# File lib/active_record/connection_adapters/schema_cache.rb, line 436 def ignored_table?(table_name) ActiveRecord.schema_cache_ignored_table?(table_name) end
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# File lib/active_record/connection_adapters/schema_cache.rb, line 461 def open(filename) FileUtils.mkdir_p(File.dirname(filename)) File.atomic_write(filename) do |file| if File.extname(filename) == ".gz" zipper = Zlib::GzipWriter.new file zipper.mtime = 0 yield zipper zipper.flush zipper.close else yield file end end end
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# File lib/active_record/connection_adapters/schema_cache.rb, line 428 def tables_to_cache(pool) pool.with_connection do |connection| connection.data_sources.reject do |table| ignored_table?(table) end end end