informix 查当天数据是怎么查的,试过一些函数但不成功,请教
id plan_res_id sign_time sign_longitude sign_latitude sign_state error_range status
-------------------------------- -------------- -------------------- ----------------- ---------------- ------------- -------------- ---------
402880f7393285c00139329bf6a9000c 1 2012-8-17 上午11:24:05 -122.084095 37.422005 1 (null) 1
402880f7393285c0013932a01d92000d 1 2012-8-17 上午11:28:37 -122.084095 37.422005 1 (null) 0
402880f7393285c0013932b392f1000e 1 2012-8-17 上午11:49:53 -122.084095 37.422005 1 (null) 1
这是数据,我要查sign_time =today,这个条件怎么写,我的日期是字符