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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e31d2dd5c6a6e3e0d3f2585d2c7568ae59ff2e6a57fdbde29076f4d3c3af1cf3' 
  AND token = '6r/+O4N5/GmUrtgH5v0/lGPQTUO+FHwD5n9ArQaTU14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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