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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4d02fb52c06e97c4f0cfb30dfff6a4fedcca7a2eca2049c6fd31009c89f54a7' 
  AND token = 'rdga0M5EUMYbPLwVjD2K1rKHJ+dkIoXAtiraBQ0D5Yg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}