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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f753399cb5a0989a96633aa6a8ab4560077dde3e6d58b84b8dd4ed2acf7dbe55' 
  AND token = 'KfcMELBmXM0ESa04ApJWY+g5OS8JSshzcKQ/ZiZ7G6s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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