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ST_attrTimestampFilter

更新时间:

指定轨迹属性字段,根据固定值,过滤出符合条件的轨迹点,返回过滤后的属性字段值(数组)。

语法

timestamp[] ST_attrTimestampFilter(trajectory traj, cstring attr_field_name,cstring operator, timestamp value);
timestamp[] ST_attrTimestampFilter(trajectory traj, cstring attr_field_name,cstring operator, timestamp value1, timestamp value2);

参数

参数名称

描述

traj

轨迹对象。

attr_field_name

指定的属性名称。

operator

过滤符,'=''!=''>''<''>=''<=''[]''(]''[)''()'

value、value1

属性固定值下限。

value2

属性固定值上限。

示例

insert into traj values(3,ST_makeTrajectory('STPOINT'::leaftype, st_geomfromtext('LINESTRING (114 35, 115 36, 116 37)', 4326), ARRAY['2010-01-01 14:30'::timestamp, '2010-01-01 15:00', '2010-01-01 15:30'], '{"leafcount": 3, "attributes" : {"heading" : {"type": "timestamp", "nullable" : false,"value":["Fri Jan 01 14:30:00 2010", "Fri Jan 01 15:00:00 2010", "Fri Jan 01 15:30:00 2010"]}}}'));
select st_attrTimestampFilter(traj, 'heading', '>', 'Fri Jan 01 15:00:00 2010'::timestamp) from traj where id = 3;
 st_attrtimestampfilter  
------------------------- 
{"2010-01-01 15:30:00"}
(1 row)