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SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ac17b1c1d64533a8c75f0e17eafcc4e68264601e7084490dc66933e88ad2768a' 
  AND token = 'TvR6ZTiw/MZ1g2Bksi5TRf3c8R+t1QqwQJQpYAB9RmU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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