quadbinQuerySource

You can use quadbinQuerySource to build layers and widgets using custom SQL queries powered by your data warehouse that contain:

• Quadbin-based data: a column containing a Quadbin cell identifier

• Point-based vector data

When you use point-based vector data in your quadbinQuerySource, CARTO will dynamically aggregate it into Quadbin cells, using an aggregation expression of your choice.

Usage

import {quadbinQuerySource} from '@carto/api-client';

const data = quadbinQuerySource({
  accessToken: 'XXX',
  connectionName: 'carto_dw',
  sqlQuery: 'SELECT * FROM carto-demo-data.demo_tables.quadbin_table',
  aggregationExp: 'SUM(population)'
});

Options

type QuadbinTableSourceOptions = {
  tableName: string;
  aggregationExp: string;
  aggregationResLevel?: number;
  spatialDataColumn?: string;
  filters?: Filters;
  filtersLogicalOperator?: 'and' | 'or'; 
  queryParameters?: QueryParameters;
};

• tableName: The fully qualified name (FQN) of the table you want to retrieve from your data warehouse. For example, for a BigQuery connection, carto-demo-data.demo_tables.quadbin_sample would be a valid table name.

• aggregationExp: A valid SQL expression that will define how this source aggregates quadbin cells starting from the base resolution into each parent quadbin cell in lower zoom levels. For example, for an aggregationExp containing AVG(income) , each parent quadbin cell will contain the average income from all its children.

  • For point-based, this defines the aggregation of the points for every zoom level.

• aggregationResLevel (optional): A number that expresses the resolution detail that will be used for each zoom level. By default this value is 6 .

  • Numbers lower than 6 will produce a less detailed visualization, with better performance.

  • Numbers higher than 6 will product a more detailed visualization, with worse performance.

• spatialDataColumn (optional): The name of the column that contains the geospatial information (geometries/geographies) that will be used for visualization and etc. By default, CARTO assumes this column is named geom.

• filters (optional): A valid CARTO Filters object, used to perform server-side filtering of this data source with column-based filters.
• filtersLogicalOperator (optional): Indicates whether filters are applied following an AND logic or an OR logic.

• queryParameters (optional): If your sqlQuery contains query parameters, pass the values for each parameter in this field, following your data warehouse mechanism for query parameters, like named or positional parameters.

About queryParameters and parameterized queries

CARTO uses the native mechanisms available in each data warehouse to build parameterized queries, which prevents any SQL injection.

Therefore, to specify the parameters in the query and the expected syntax for queryParameters , you will need to use the specific providers' syntax:

BigQuery

BigQuery uses named parameters.

sqlQuery: 'SELECT * FROM carto-demo-data.demo_tables.retail_stores WHERE storetype = @type AND revenue > @minRevenue'
queryParameters: { 'minRevenue': 100000, 'type': 'Supermarket' },

Please note that empty arrays are not supported as parameter values.

Snowflake

Snowflake supports positional parameters, such as:

sqlQuery: 'SELECT * FROM demo_db.public.import_retail_stores WHERE storetype = :2 AND revenue > :1'
queryParameters: [100000, "Supermarket"],

Redshift and PostgreSQL

Snowflake supports positional parameters, such as:

sqlQuery: 'SELECT * FROM carto_demo_data.demo_tables.retail_stores WHERE storetype = $2 AND revenue > $1...'
queryParameters: [100000, "Supermarket"],

Response

The response of quadbinQuerySource is a promise that can be resolved and used in layers and widgets.

Connection compatibility

Connection Data Warehouse	Compatible
BigQuery	✅
Snowflake	✅
Redshift	✅
Databricks	✅
PostgreSQL	✅
CARTO Data Warehouse	✅

Layer compatibility

quadbinQuerySource is compatible with the following layers from the @deck.gl/carto module:

• QuadbinTileLayer

Widget model compatibility

quadbinQuerySource is compatible with the following widget models:

• getFormula
• getCategories
• getHistogram
• getRange
• getScatter
• getTimeSeries
• getTable