更改某條軌跡的空間參考標識符（SRID）。
文法
trajectory ST_SetSRID(trajectory traj, int srid);參數
| 參數名稱 | 描述 |
| traj | 軌跡對象。 |
| srid | 目標SRID。 |
描述
將軌跡的SRID設定為給定的值，但不更改其它內容。
樣本
select ST_setSRID('{"trajectory":{"version":1,"type":"STPOINT","leafcount":2,"start_time":"2007-05-27 00:00:00","end_time":"2007-05-28 08:36:47.846","spatial":"SRID=4326;LINESTRING(13.43593 52.41721,13.43593 52.41721)","timeline":["2007-05-27 00:00:00","2007-05-28 08:36:47.846"]}}'::trajectory
,4002);
st_setsrid
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
{"trajectory":{"version":1,"type":"STPOINT","leafcount":2,"start_time":"2007-05-27 00:00:00","end_time":"2007-05-28 08:36:48","spatial":"SRID=4002;LINESTRING(13.43593 52.41721,13.43593 52.41721)","timeline":["2007-05-27 00:00:00","2007-05-28 08:36:48"]}}
(1 row)