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SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '521b3c7dc604fc2ccc68d3e2444d5ffbb3d5477a7f75dec9fcdd148e0ce8e3c5' 
  AND token = '7Rp4nSP7pNC/6+zCybPw4GDHftA6+LrOaczvl6ErHAI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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