Vertica Blog

Vertica Blog

Vertica Blog

Vertica Quick Tip: VSQL Shortcuts to Move Faster on the Command Line

This blog post was authored by Jim Knicely. vsql is Vertica’s character-based, interactive, front-end utility that lets you type SQL statements and see the results. If you’ve typed a particularly long query in vsql then realize that you’d have a typo way back at the beginning of your code (i.e. you wrote SEELECT), instead of...

Improve the Efficiency of Mergeout on Wide Tables

This blog post was co-authored by Xiao Ling and Jim Kelley. Introduction When resource pools were first introduced to Vertica, the average computer had a lot less memory than it does today. The default memory size for the Tuple Mover resource pool, 200 MB, reflects the more limited resources of that period. As hardware and...

Vertica Quick Tip: Renaming a View

This blog post was authored by Jim Knicely. You are probably aware that you can rename a table using the ALTER TABLE … RENAME command. But you might not know that you can just as easily rename a database view using a very similar command! Have fun!
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North East Database Day Conference

This blog post was authored by Eden Zik. On January 19th, Vertica engineers joined the North East database community for the North East Database Day conference organized annually at MIT, sponsored by Facebook and Microsoft and featuring Turing award winner Michael Stonebraker. The full conference program can be found here: This year Styliani Pantela from...

Vertica Quick Tip: Viewing Query Error Information

This blog post was authored by Jim Knicely. The V_MONITOR.ERROR_MESSAGES system table tracks error and warning messages encountered while processing queries. If you need a bit more info, like the cursor position of a syntax error, you can query the data collector table DC_ERRORS. Have fun!

Vertica Quick Tip: Setting a Client Connection Label

This blog post was authored by Jim Knicely. When you connect to a Vertica database you can set a client connection label to help you later identify the connection. Have fun!
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Vertica Customer Experience Survey

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Vertica Quick Tip: Analyzing Table Statistics by Column

This blog post was authored by Jim Knicely. The ANALYZE_STATISTICS function collects and aggregates data samples and storage information from all nodes that store projections associated with the specified table. On a very large wide table it will take a significant amount of time to gather those statistics. In many situations only a few columns...

Vertica Tip: The System Table for System Tables

This blog post was authored by Sarah Lemaire. Most of you probably know that Vertica provides system tables that allow you to monitor • System resources • Background processes • Workload • Performance • Catalog size These tables help you to profile, diagnose, and view historical data equivalent to load streams, query profiles, Tuple Mover...

Identifying Projection Skew

This blog post was authored by Curtis Bennett. In Vertica, projections can either be replicated (unsegmented), or segmented. A segmented projection divides the data up across all the nodes in your cluster. Segmentation works by hashing a key value, and then using some simple math, figuring out which node that piece of data will live...

What Projections are not Being Used

This blog post was authored by Eugenia Moreno. It is common to create new projections to improve performance in Vertica. However, you might forget about the old projections. Vertica still loads data in projections that you might not be using. A projection that is loaded but not picked up by the Vertica optimizer consumes storage...

Vertica Quick Tip: Sampling Data from the Entire Table

This blog post was authored by Jim Knicely. A development or quality assurance team often times requests access to a sub-set of production data. One way to do that would be to make use of the LIMIT clause. The problem with that method is the team won’t get a very good sampling of the data....