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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03f8557975863acd2c3f7077d7c8b6307bde314aabd1edb01a1612e5bc6ceb6c' 
  AND token = 'Xhwhd7XqcL+H0w3ajg2AFy4Esifgv+b4jAO8hX4GI1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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