=== STRUCTURE eex_symbols_reference ===
  - id: int(11)
  - symbol_native: varchar(255)
  - symbol_api_format: varchar(255)
  - symbol_stored_format: varchar(255)
  - symbol_type: enum('FUTURES','SPOT','POWER_SPOT')
  - market_category: enum('POWER','GAS','EUA','CO2')
  - country_code: varchar(10)
  - country_name: varchar(50)
  - product_type: enum('BASE','PEAK','DAY_AHEAD','WEEKEND','NEXT_DAY')
  - period_type: enum('YEAR','QUARTER','MONTH','SEASON','DAILY')
  - exchange_name: varchar(50)
  - description_fr: text
  - description_en: text
  - is_active: tinyint(1)
  - created_at: timestamp
  - updated_at: timestamp

=== ÉCHANTILLON DONNÉES ===
Array
(
    [id] => 1
    [symbol_native] => /E.F7BYF{year}
    [symbol_api_format] => "/E.F7BYF{year}"
    [symbol_stored_format] => /E.F7BYF{year}
    [symbol_type] => FUTURES
    [market_category] => POWER
    [country_code] => F7
    [country_name] => France
    [product_type] => BASE
    [period_type] => YEAR
    [exchange_name] => EEX
    [description_fr] => Futures électricité France Base - Année
    [description_en] => France Power Base Load Futures - Year
    [is_active] => 1
    [created_at] => 2026-01-27 09:42:10
    [updated_at] => 2026-01-27 09:42:10
)
Array
(
    [id] => 2
    [symbol_native] => /E.F7BQF{year}
    [symbol_api_format] => "/E.F7BQF{year}"
    [symbol_stored_format] => /E.F7BQF{year}
    [symbol_type] => FUTURES
    [market_category] => POWER
    [country_code] => F7
    [country_name] => France
    [product_type] => BASE
    [period_type] => QUARTER
    [exchange_name] => EEX
    [description_fr] => Futures électricité France Base - Trimestre
    [description_en] => France Power Base Load Futures - Quarter
    [is_active] => 1
    [created_at] => 2026-01-27 09:42:10
    [updated_at] => 2026-01-27 09:42:10
)
Array
(
    [id] => 3
    [symbol_native] => /E.F7BMF{year}
    [symbol_api_format] => "/E.F7BMF{year}"
    [symbol_stored_format] => /E.F7BMF{year}
    [symbol_type] => FUTURES
    [market_category] => POWER
    [country_code] => F7
    [country_name] => France
    [product_type] => BASE
    [period_type] => MONTH
    [exchange_name] => EEX
    [description_fr] => Futures électricité France Base - Mois
    [description_en] => France Power Base Load Futures - Month
    [is_active] => 1
    [created_at] => 2026-01-27 09:42:10
    [updated_at] => 2026-01-27 09:42:10
)