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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf8211fe2cc4b49b7f0874a73609908f23dc0067f804b301fbfeb4035fa2d52e' 
  AND token = 'bKkK1PgP2CCBFf8a0ifCp9VLiREYbhC1YRsYiWDN9JQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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