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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '390953cbbe77bf75df9c3863c1138249d7cb136f8e2d1c8e7389eb329eaf3ce0' 
  AND token = 'br6+j81a2IqL9SoR7lN4ha5WP9WrSVMCr5ThcrZ8EhI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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