Thanks Hans, Yes, SQLUDR_CHAR can support input/output values as TIMESTAMP. This solves my problem. So Trafodion UDF can support TIMESTAMP as both input parameter and output , this is great!
Thanks, Ming 发件人: Hans Zeller [mailto:hans.zel...@esgyn.com] 发送时间: 2016年3月24日 1:34 收件人: user@trafodion.incubator.apache.org 主题: Re: How to implement a TO_DATE UDF in Trafodion Hi Ming, I think the C data type corresponding to datetime values is SQLUDR_CHAR. You create a string that looks like "2016-03-23 01:23:45" (this example is for a TIMESTAMP(0)) and return that. Trafodion will convert it to the datetime type. Sorry, I have not tested it but hope it will work. Hans On Thu, Mar 17, 2016 at 8:43 PM, Liu, Ming (Ming) <ming....@esgyn.cn<mailto:ming....@esgyn.cn>> wrote: Hi, all, I just learned the support of TO_DATE will be avialbe in Trafodion in R2.0 from Anoop, that is great! At present, due to the urgent requirement of current migration project, we cannot wait, so I want to write a UDF to do the TO_DATE. When I try to write it, I found it seems the UDF can only return simple data type like INT, VARCHAR, I cannot find the definition of returning a TIMESTAMP/DATE, could anyone help here? In sqludr.h , I cannot find corresponding data type for DATE/TIMESTAM. So I don’t know how to define the UDF’s entry function, example as below: SQLUDR_LIBFUNC SQLUDR_INT32 to_date(SQLUDR_VC_STRUCT *srcStr, //input string SQLUDR_CHAR *pattern, //date format ??? *out1, //the output SQLUDR_INT16 *inInd1, SQLUDR_INT16 *inInd2, SQLUDR_INT16 *outInd1, SQLUDR_TRAIL_ARGS) How can I specify the out1 type to be a DATE or TIMESTAMP? I marked with ‘???’ . Thanks in advance, Ming
