Glossary
Help
 Archive Intro
 Table Descriptions
 Schema Browser
 Glossary
 Algorithms
 Introduction to SQL
 Form Query User Guide
 Query Limits
 How To
 FAQ
 API
 sdssQA
 Download
 SkyServer Sites
 Web Browsers
 Contact Help Desk

nametext
flagA bitmask used in the database to specify various properties of an object. There are many flags in the SDSS catalogs which tell the user extremely important and useful pieces of information, such as whether the object was deblended or saturated, for instance. There are status flags set by PSP, and by survey operations, on a frame-by-frame basis, describing the quality of the PSF, and the quality of the data overall. Each object is given status flags that sort out overlaps. And the spectra have flags at two levels as well: pixel-by-pixel flags, and warning flags accompanying the redshifts and classification to indicate trouble.