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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'f42b2fa0dcfb8a740a38e5540ff7bfebc2075c31a8e6a08d6072816301a4d7aa' 
  AND token = 'mGmdenP3/+MESLWkMJmuC3STP2FjIEoRE85nl6P9WRM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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