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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '83b936cf1c6df2bc615a07fd7bbd72ac0794b6d5ef6c1f73193ba5f2c014c93d' 
  AND token = 'dCkjrux3hDMDxsw3RsDhr7Jp+qVoHgR6JAn4UtRtDSQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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