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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df7f69a392072fe7b1b6b37da0487859ffd4e3d8fbdaf439fee29ee1f7d34c13' 
  AND token = '9fDjJW+Y4Awk+H19dqUcYaWrqTa8Bo7wrV904HClv38=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}