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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc912f9b4df8cee532e05c1d1cd0fa59fe2a4f208e29e0e8c6c9c2ff539b1513' 
  AND token = 'z0ZPkdduUceIIoExmTLLlU+i41X2v+0IzpZoCskb/2g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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