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title: Foreign Data Wrappers, Aggregate Filters, Smart City project, and more.
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The Crunchy Data Newsletter is full of valuable Postgres content every month.

| View in browser Special Series on Foreign Data Wrappers Understanding Foreign Data Wrappers in Postgres and postgres\_fdw This blog provides a nice overview of using foreign data wrappers to connect to external Postgres sources. Find out how to query across multiple datasets like they're in the same database.    Querying Spatial Data with PostGIS and ogr\_fdw Review some of the ways to use foreign data wrappers with PostGIS using the ogr\_fdw extension to connect to a repository of shapefiles. This works even inside externally hosted zip files.    From our Blog Devious SQL: Message Queuing Using Native PostgreSQL Ever need to queue messages or information coming in? Using native Postgres is an option and this post explains how it is possible.    Insert-Only Tables and Autovacuum Issues Prior to PostgreSQL 13 Vacuum processes for insert-only tables might work differently than you expect in Postgres versions prior to 13. Learn about how that can impact performance on read replicas and what you can do to solve it.    Fast, Flexible Summaries with Aggregate Filters and Windows Paul Ramsey shows us a great summary of what you can do with aggregate filters and window functions for large datasets. We have some easy methods in here for extracting quick summaries.    Waiting for PostGIS 3.2: Secure Cloud Raster Access Hosting raster files in the cloud in an out-db model with the GDAL library has become commonplace. The upcoming release of PostGIS 3.2 addresses some much needed access control on cloud repositories.    Demo Building a Metro HA Postgres Cluster with OpenShift Data Foundation Andrew L'Ecuyer of Crunchy Data and Annette Clewett of Red Hat show off a Smart City vehicle project using OpenShift, ODF, Kafka, and our Postgres Operator for Kubernetes.   Upcoming Events FOSS4G 2021: September 27-October2 FOSS4G (Free and Open Source Software for Geospatial) will be hosting their annual event online this year and Crunchy Data is sponsoring their efforts.    AnsibleFest 2021: September 29-30 Crunchy Data is sponsoring the annual AnsibleFest (virtual) conference. Between automation talks, join us at our virtual booth. Crunchy Data, 162 Seven Farms Drive, Suite 220, Charleston, SC 29492, 843-737-6045 Unsubscribe Manage preferences |
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