REQUIREMENT_OK

drupal_requirements_severity in core/includes/install.inc

Extracts the highest severity from the requirements array.

LocaleRequirements::runtime in core/modules/locale/src/Hook/LocaleRequirements.php

Implements hook_runtime_requirements().

MysqlRequirements::runtime in core/modules/mysql/src/Hook/MysqlRequirements.php

Implements hook_runtime_requirements().

mysql_requirements in core/modules/mysql/mysql.install

Implements hook_requirements().

PgsqlRequirements::getRequirements in core/modules/pgsql/src/Install/Requirements/PgsqlRequirements.php

Check installation requirements.

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