Create a KQL database

In Real-Time Intelligence, you interact with your data in the context of eventhouses, databases, and tables. A single workspace can hold multiple Eventhouses, an eventhouse can hold multiple databases, and each database can hold multiple tables.

In this article, you learn how to create a new KQL database. Once your KQL database has data, you can proceed to query your data using Kusto Query Language in a KQL queryset.

Prerequisites

Create a new KQL database

  1. To create a new KQL database, in the Eventhouse explorer either:

    • Select Eventhouse then New database +

    • Under KQL Databases select +

      Screenshot showing the eventhouse KQL Databases section.

  2. Enter your database name, select your database type, either New database (default) or New shortcut database (follower), then select Create. For information about follower databases, see Create a database shortcut.

    Note

    The database name can contain alphanumeric characters, underscores, periods, and hyphens. Special characters aren't supported.

    Screenshot of the New KQL Database window showing the database name. The Create button is highlighted.

The KQL database is created within the context of the selected eventhouse.

Explore your KQL database

When you create a new KQL database, an attached environment is automatically created to explore and manage the KQL database using KQL queries. For more information, see KQL overview.

  1. To access the query environment, select KQLdatabasename_queryset from your KQL database object tree.

    Screenshot of new attached KQL queryset to a KQL database.

  2. To rename the query environment, select the Pencil icon next to its name, and enter a new name.

    Screenshot of the Rename queryset window showing the queryset name and the Pencil icon.

Database details

The main page of your KQL database shows an overview of the contents of your database. The following tables list the available information in the center and right information panes.

Screenshot of KQL database main page showing the database details cards.

Database right pane details

The right information pane displays the details of the selected database.

Card Item Description
Size
Compressed Total size of compressed data.
Original size Total size of uncompressed data.
OneLake
Availability Set OneLake availability to On or Off. When OneLake availability is turned on, tables can't be renamed.
Latency The maximum time until data is available across tables in OneLake.
Table number The number of tables available in OneLake.
OneLake folder OneLake folder path that can be used for creating shortcuts.
Overview
Created by The user name of person who created the database, if available, and the database creation date.
Region Shows the region where your capacity is hosted. For more information, see Fabric region availability.
Query URI The URI used to run queries or management commands.
Ingestion URI The date of the last data ingestion and the URI that can be used to get data.
Caching Policy The time period in which data is cached and kept in local SSD storage. For more information, see Caching policy.
Retention Policy The time period after which data is automatically removed from tables or materialized views. For more information, see Data retention policy.

Database center information pane

The center database information pane depicts a histogram of the ingestion data, table information, and a means to preview the database ingestion information.

Card Item Description
Histogram
Number of rows The number of rows loaded into the database in the selected time range.
Last run The time when the histogram was last generated.
Interval Set the interval of the histogram display. Set intervals by one hour, six hours, one day, three days, seven days, and 30 days.
Refresh Refresh your histogram.
Histogram The ingestion histogram displays data by the interval chosen. The interval is calculated by a full coordinated universal time (UTC) day, but displays according to the local time.
Tables
Search for table Search for a database table.
New table Create a new table
Tables display View table information by Cards or by List view.

Cards and list view both display table name, Compressed size, Last ingestion, and OneLake availability or latency.

Cards uniquely display a histogram of the database ingestion over the past seven days, the number of rows ingested in the last ingestion, and the table creator profile.

The list view display also shows total Row count, Caching, and Retention.
Data preview
Data preview Shows a preview of the last 100 records ingested for each table. Displays Ingestion time, TableName, and Record. Select Columns to select columns and values for a Pivot view.

Table details

Select a table in your KQL database to see an overview of the table. The following tables list the available information in the center and right information panes.

Table right pane details

The right information pane displays the details of the selected table.

Card Item Description
Size
Compressed Total size of compressed data.
Original size Total size of uncompressed data.
OneLake
Availability Set OneLake availability to On or Off. When OneLake availability is turned on, tables can't be renamed.
Latency The maximum time until table data is available in OneLake.
Since The start time from when availability is recorded.
OneLake folder OneLake folder path that can be used for creating shortcuts.
Overview
Row count The number of rows in the table.
Rows ingested last 24 h The number of rows ingested in the last 24 hours.
Schema last altered by When the schema was last altered and by whom.
Ingestion URI The date of the last data ingestion and the URI that can be used to get data.
Caching Policy The time period in which data is cached and kept in local SSD storage. For more information, see Caching policy.
Retention Policy The time period after which data is automatically removed from tables or materialized views. For more information, see Data retention policy.

Table center information pane

The center database information pane depicts a histogram of the ingestion data, table information, and a means to preview the database ingestion information.

Card Item Description
Histogram
Number of rows The number of rows ingested into the database.
Last run The time when the histogram was last generated.
Interval Set the interval of the histogram display. Set intervals by one hour, six hours, one day, three days, seven days, and 30 day intervals. The interval is calculated by a full coordinated universal time (UTC) day, but displays according to the local time.
Refresh Refresh your histogram.
Histogram The ingestion histogram displays data by the interval chosen.
Data preview
Quick query Shows a preview of the table ingestion results. Displays Ingestion time, TableName, and Record. Select Columns to select columns and values for a Pivot view.
Schema insights
Columns For each column in a table, shows insights for column values, such as date ranges, minimum and maximum values, or the number of unique values.
Top 10 Select a column listed in the Columns section to display the top 10 values for that column.

Screenshot of KQL table page showing the table details cards.