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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec547d1c154e9212d34c2c487dbcf76b2cb954cd8a7820ca1f81325c50318722' 
  AND token = 'CoV5Wf3TPS5PPiVzxxtBuBK5KX+ah9Wc5ktOVf4SYbo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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