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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5a0dd639f1e290c0775d0d0387a1490dc003925cd65eebbd2cf33234fcb5c05' 
  AND token = 'y8YdcMLaK3XPrvH3UjlWrkmsR0jbQ8Sgid7NtgH2DOo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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