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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52cdf7e9cc44972a09007687a35654d1f9c4276e62666c1644d8f52dc6da58c2' 
  AND token = 'vVZ21ER7Nq2CgCghJIR98mNjShSxeMRl0aa1KNspjoo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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