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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3cb0723f5cf66c57a036bee6cefa590ce02cfc1ee2a2e206d6be48a82aea93e' 
  AND token = 'kVT4uuiKV2NtNyoNVrE3F3Uj1tAPVqbFGvYlc3oZIRc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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