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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68d5142b0e4eb47fb0bb98a5048caaf8aa800e63bbcc67eb66dbac587d100241' 
  AND token = 'kRCdZ+RSwSS2t4CocmhxBNo1mEE0QOO+udaA5yH1RXQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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