PGXC_GET_TABLE_SKEWNESS
PGXC_GET_TABLE_SKEWNESS displays the data skew on tables in the current database. Only the system administrator or the preset role gs_role_read_all_stats can access this view.
You are advised to use PGXC_GET_TABLE_SKEWNESS to query data skew when there are less than 10,000 tables in a database.
Column | Type | Description |
|---|---|---|
schemaname | Name | Schema name of a table |
tablename | Name | Name of a table |
totalsize | Numeric | Total size of a table, in bytes |
avgsize | numeric(1000,0) | Average table size (total table size divided by the number of DNs), which is the ideal size of tables distributed on each DN |
maxratio | numeric(10,3) | Ratio of the maximum table size on a single DN to the value of avgsize. |
minratio | numeric(10,3) | Ratio of the minimum table size on a single DN to avgsize |
skewsize | Bigint | Table skew rate (the maximum table size on a single DN minus the minimum table size on a single DN) |
skewratio | numeric(10,3) | Table skew rate (skewsize/avgsize) |
skewstddev | numeric(1000,0) | Standard deviation of table distribution (For two tables of the same size, a larger deviation indicates a more severe skew.) |
Feedback
Was this page helpful?
Provide feedbackThank you very much for your feedback. We will continue working to improve the documentation.
