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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6b6039a9aa7c5bdba2a13bb30681e0cbab63c25b5fc2c1e88346abc16aff639' 
  AND token = 'n5hQi+shdTRPWWWoagqgcP2CRowEtRSHDAxeqzum+P8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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