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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a5f3e5c4f91f2cf98898f447dea8b58d31f4a4edcf60ac183efe6f18c22ade5d' 
  AND token = '6w/ZZ1PlmoB6L9XpuMYfg4t5G01qUr80AqdNStL3tFQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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