SingleStore Managed Service

mv_query_column_usage

The mv_query_column_usage view in the information_schema database provides information about the usage of columns by queries in the workload. Details about column that are used in joins, filters, group-bys, order-bys or reshuffles help to understand the frequency and cost of use of columns, and make better decisions about indexing and sharding of data.

Column name

Description

activity_name

The ID associated with the query. This will be the activity_name of all query tasks associated with the query.

database_name

The name of the database, or NULL if none could be assigned.

table_name

The name of the table in the query.

column_name

The name of the column that exists in the table.

equijoins

The number of times this column was involved in an equijoin in the query.

non_equijoins

The number of times the column was involved in a non-equijoin in the query.

equality_preds

The number of times the column was involved in equality predicates in the WHERE or ON clause in the query.

inequality_preds

The number of times the column was involved in inequality predicates in the WHERE or ON clause in the query.

groupbys

The number of times the column was involved in a GROUP BY clause in the query.

orderbys

The number of times the column was involved in a ORDER BY clause in the query.

reshuffles

The number of times the column was member of reshuffle key in the query.

outputs

The number of times the column was returned as the result of the query.