GiST indexing-AnalyticDB(AnalyticDB)-阿里云帮助中心

Create a Generalized Search Tree (GiST) index on a trajectory data column to accelerate spatial queries on that column.

How it works

The following functions automatically use the GiST index when one is available:

ST_ndIntersect
ST_ndDWithin
ST_ndContains
ST_ndWithin

Syntax

CREATE INDEX [index_name] ON table_name USING GIST(traj_col [operator_family]);

Parameter	Required	Description
`index_name`	No	Name of the index
`table_name`	Yes	Name of the table that contains the trajectory column
`traj_col`	Yes	Name of the trajectory column
`operator_family`	No	Operator family that determines which axes are indexed. Default: `trajgist_ops_3dt`

The default operator family trajgist_ops_3dt indexes all four axes (x, y, z, and t) and supports every query type. If your queries consistently target a smaller set of axes, specify a narrower operator family. Fewer indexed dimensions generally produce faster queries.

Supported operator families

Operator family	Indexed axes	Supported query types
`trajgist_ops_z`	z	z-axis queries
`trajgist_ops_t`	t	t-axis queries
`trajgist_ops_2d`	x, y	x- and y-axis queries
`trajgist_ops_2dt`	x, y, t	x- and y-axis queries; t-axis queries; x-, y-, and t-axis queries
`trajgist_ops_3d`	x, y, z	x- and y-axis queries; z-axis queries; x-, y-, and z-axis queries
`trajgist_ops_3dt`	x, y, z, t	All query types supported by the preceding five operator families

Examples

The following examples create indexes optimized for specific query patterns.

-- Index on the t axis only — for time-range queries
CREATE INDEX ON table_name USING GIST(traj_col trajgist_ops_t);

-- Index on the x and y axes — for 2D spatial queries
CREATE INDEX ON table_name USING GIST(traj_col trajgist_ops_2d);

-- Index on the x, y, and t axes — for spatiotemporal queries without elevation
CREATE INDEX ON table_name USING GIST(traj_col trajgist_ops_2dt);