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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6c2b8ccb6605fc440b9b59ff8851f048dcb19cc6210238c0b28ec4c95b2a2cfe' 
  AND token = 'PXq8EMnwZ/BWSCd/2r45krSr4oX34RyhCOGKXjMrCM4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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