wordpress transients codex code example
Example 1: transient wordpress
MINUTE_IN_SECONDS = 60 (seconds)
HOUR_IN_SECONDS = 60 * MINUTE_IN_SECONDS
DAY_IN_SECONDS = 24 * HOUR_IN_SECONDS
WEEK_IN_SECONDS = 7 * DAY_IN_SECONDS
MONTH_IN_SECONDS = 30 * DAY_IN_SECONDS
YEAR_IN_SECONDS = 365 * DAY_IN_SECONDS
Example 2: transient wordpress
set_transient( 'special_query_results', $special_query_results, 60*60*12 );