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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df3f4e6f0b9b528d4cc962a5f1e2775e800aa60f6fd2d0a32ddb27ed303269ca' 
  AND token = '76gWwNOKNYoHW/HgvliQKywpNSc8as9UVQdbrnCSsXM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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