Geo queries are classified into the following types: geo-distance query, geo-bounding box query, and geo-polygon query.
Prerequisites
An OTSClient instance is initialized. For more information, see Initialize an OTSClient instance.
A data table is created and data is written to the data table. For more information, see Create a data table and Write data.
A search index is created for the data table. For more information, see Create a search index.
Geo-distance query
To perform a geo-distance query, specify a circular geographic area by using a central point and a radius. Tablestore returns the rows in which the value of a specific column falls within the circular geographic area.
Parameters
Parameter Description fieldName The name of the column. Set the query type to Geopoint. centerPoint The coordinate pair of the central point. The coordinate pair consists of latitude and longitude values. This parameter value must be in the format of
latitude,longitude
. Valid values of the latitude: [-90,+90]. Valid values of the longitude: [-180,+180]. Example:35.8,-45.91
.distanceInMeter The radius of the circle centered on the specified location. Type: DOUBLE. Unit: meter. getTotalCount Specifies whether to return the total number of rows that match the query conditions. By default, this parameter is set to false, which indicates that the total number of rows that match the query conditions is not returned. Query performance is affected when this parameter is set to true.
query The query statement for the search index. Set the query type to GeoDistanceQuery. tableName The name of the table. indexName The name of the search index. columnsToGet Specifies whether to return all columns of each matched row. You can configure returnAll and columns for this parameter. By default, returnAll is set to false, which indicates that not all columns are returned. If returnAll is set to false, you can use columns to specify the columns to return. If you do not specify the columns to return, only the primary key columns are returned.
If returnAll is set to true, all columns are returned.
Examples
The following sample code provides an example on how to query rows in which the value of the Col_GeoPoint column is within a specific distance from the central point.
public static void geoDistanceQuery(SyncClient client) { SearchQuery searchQuery = new SearchQuery(); GeoDistanceQuery geoDistanceQuery = new GeoDistanceQuery(); // Use GeoDistanceQuery. geoDistanceQuery.setFieldName("Col_GeoPoint"); geoDistanceQuery.setCenterPoint("5,5"); // Specify the coordinates of the central point. geoDistanceQuery.setDistanceInMeter(10000); // Set the distance from the central point to a value greater than or equal to 10,000. Unit: meter. searchQuery.setQuery(geoDistanceQuery); //searchQuery.setGetTotalCount(true); // Set the GetTotalCount parameter to true to return the total number of rows that meet the query conditions. SearchRequest searchRequest = new SearchRequest("<TABLE_NAME>", "<SEARCH_INDEX_NAME>", searchQuery); // You can use the columnsToGet parameter to specify the columns that you want to return or specify that all columns are returned. If you do not specify this parameter, only the primary key columns are returned. //SearchRequest.ColumnsToGet columnsToGet = new SearchRequest.ColumnsToGet(); //columnsToGet.setReturnAll(true); // Specify that all columns are returned. //columnsToGet.setColumns(Arrays.asList("ColName1","ColName2")); // Specify the columns that you want to return. //searchRequest.setColumnsToGet(columnsToGet); SearchResponse resp = client.search(searchRequest); //System.out.println("TotalCount: " + resp.getTotalCount()); // Display the total number of rows that meet the query conditions instead of the number of rows that are returned. System.out.println("Row: " + resp.getRows()); }
Geo-bounding box query
To perform a geo-bounding box query, specify a rectangular geographic area by using an upper-left corner and a lower-right corner. Tablestore returns the rows in which the value of a specific column falls within the rectangular geographic area.
Parameters
Parameter Description fieldName The name of the column. Set the query type to Geopoint. topLeft The coordinate pair of the upper-left corner of the rectangular geographic area. bottomRight The coordinate pair of the lower-right corner of the rectangular geographic area. The coordinate pairs of the upper-left corner and lower-right corner define a unique rectangular geographic area. This parameter value must be in the format of
latitude,longitude
. Valid values of the latitude: [-90,+90]. Valid values of the longitude: [-180,+180]. Example:35.8,-45.91
.query The query statement for the search index. Set the query type to GeoBoundingBoxQuery. getTotalCount Specifies whether to return the total number of rows that match the query conditions. By default, this parameter is set to false, which indicates that the total number of rows that match the query conditions is not returned. Query performance is affected when this parameter is set to true.
tableName The name of the table. indexName The name of the search index. columnsToGet Specifies whether to return all columns of each matched row. You can configure returnAll and columns for this parameter. By default, returnAll is set to false, which indicates that not all columns are returned. If returnAll is set to false, you can use columns to specify the columns to return. If you do not specify the columns to return, only the primary key columns are returned.
If returnAll is set to true, all columns are returned.
Examples
The following sample code provides an example on how to query rows in which the value of the Col_GeoPoint column falls within the rectangular geographic area defined by the "10,0" upper-left corner and the "0,10" lower-right corner:
public static void geoBoundingBoxQuery(SyncClient client) { SearchQuery searchQuery = new SearchQuery(); GeoBoundingBoxQuery geoBoundingBoxQuery = new GeoBoundingBoxQuery(); // Use GeoBoundingBoxQuery. geoBoundingBoxQuery.setFieldName("Col_GeoPoint"); // Specify the name of the column that you want to query. geoBoundingBoxQuery.setTopLeft("10,0"); // Specify the coordinates of the upper-left corner of the rectangular geographic area. geoBoundingBoxQuery.setBottomRight("0,10"); // Specify the coordinates of the lower-right corner of the rectangular geographic area. searchQuery.setQuery(geoBoundingBoxQuery); //searchQuery.setGetTotalCount(true); // Set the GetTotalCount parameter to true to return the total number of rows that meet the query conditions. SearchRequest searchRequest = new SearchRequest("<TABLE_NAME>", "<SEARCH_INDEX_NAME>", searchQuery); // You can use the columnsToGet parameter to specify the columns that you want to return or specify that all columns are returned. If you do not specify this parameter, only the primary key columns are returned. //SearchRequest.ColumnsToGet columnsToGet = new SearchRequest.ColumnsToGet(); //columnsToGet.setReturnAll(true); // Specify that all columns are returned. //columnsToGet.setColumns(Arrays.asList("ColName1","ColName2")); // Specify the columns that you want to return. //searchRequest.setColumnsToGet(columnsToGet); SearchResponse resp = client.search(searchRequest); //System.out.println("TotalCount: " + resp.getTotalCount()); // Display the total number of rows that meet the query conditions instead of the number of rows that are returned. System.out.println("Row: " + resp.getRows()); }
Geo-polygon query
To perform a geo-polygon query, specify a polygon geographic area by using the coordinate pairs of multiple points. Tablestore returns the rows in which the value of a specific column falls within the polygon geographic area.
Parameters
Parameter
Description
fieldName
The name of the column that you want to query. The value of this parameter is of the GEOPOINT data type.
points
The coordinate pairs of the points that define polygon geographical area.
This parameter value must be in the format of
latitude,longitude
. Valid values of the latitude:[-90,+90]
. Valid values of the longitude:[-180,+180]
. Example:35.8,-45.91
.query
The query statement for the search index. Set this parameter to GeoPolygonQuery.
getTotalCount
Specifies whether to return the total number of rows that meet the query conditions. The default value of this parameter is false, which specifies that the total number of rows that meet the query conditions is not returned.
If you set this parameter to true, the query performance is compromised.
tableName
The name of the data table.
indexName
The name of the search index.
columnsToGet
Specifies whether to return all columns of each row that meets the query conditions. You can specify the returnAll and columns fields for this parameter.
The default value of the returnAll field is false, which specifies that not all columns are returned. In this case, you can use the columns field to specify the columns that you want to return. If you do not specify the columns that you want to return, only the primary key columns are returned.
If you set the returnAll field to true, all columns are returned.
Examples
The following sample code provides an example on how to query rows in which the value of the Col_GeoPoint column falls within the specified polygon geographic area.
public static void geoPolygonQuery(SyncClient client) { SearchQuery searchQuery = new SearchQuery(); GeoPolygonQuery geoPolygonQuery = new GeoPolygonQuery(); // Use GeoPolygonQuery. geoPolygonQuery.setFieldName("Col_GeoPoint"); geoPolygonQuery.setPoints(Arrays.asList("0,0","5,5","5,0")); // Specify the coordinates of the vertices of a polygon geographic area. searchQuery.setQuery(geoPolygonQuery); //searchQuery.setGetTotalCount(true); // Set the GetTotalCount parameter to true to return the total number of rows that meet the query conditions. SearchRequest searchRequest = new SearchRequest("<TABLE_NAME>", "<SEARCH_INDEX_NAME>", searchQuery); // You can use the columnsToGet parameter to specify the columns that you want to return or specify that all columns are returned. If you do not specify this parameter, only the primary key columns are returned. //SearchRequest.ColumnsToGet columnsToGet = new SearchRequest.ColumnsToGet(); //columnsToGet.setReturnAll(true); // Specify that all columns are returned. //columnsToGet.setColumns(Arrays.asList("ColName1","ColName2")); // Specify the columns that you want to return. //searchRequest.setColumnsToGet(columnsToGet); SearchResponse resp = client.search(searchRequest); //System.out.println("TotalCount: " + resp.getTotalCount()); // Display the total number of rows that meet the query conditions instead of the number of rows that are returned. System.out.println("Row: " + resp.getRows()); }
FAQ
References
When you use a search index to query data, you can use the following query methods: term query, terms query, match all query, match query, match phrase query, prefix query, range query, wildcard query, geo query, Boolean query, KNN vector query, nested query, and exists query. You can use the query methods provided by the search index to query data from multiple dimensions based on your business requirements.
You can sort or paginate rows that meet the query conditions by using the sorting and paging features. For more information, see Perform sorting and paging.
You can use the collapse (distinct) feature to collapse the result set based on a specific column. This way, data of the specified type appears only once in the query results. For more information, see Collapse (distinct).
If you want to analyze data in a data table, you can use the aggregation feature of the Search operation or execute SQL statements. For example, you can obtain the minimum and maximum values, sum, and total number of rows. For more information, see Aggregation and SQL query.
If you want to obtain all rows that meet the query conditions without the need to sort the rows, you can call the ParallelScan and ComputeSplits operations to use the parallel scan feature. For more information, see Parallel scan.