Reflection

Unique identifier for the reflection.

Example 95dda9dd-2371-467f-b68d-fc4c5ea57a8b

Reflection type. For more information, read Types of Reflections.

Enum RAW , AGGREGATION

Example AGGREGATION

User-provided name for the reflection. For reflections created in the Dremio UI, if the user did not provide a name, the default values are Raw Reflection and Aggregation Reflection (automatically assigned based on the reflection type).

Example Aggregation Reflection

Unique identifier for the reflection instance. Dremio changes the tag whenever the reflection changes and uses the tag value to ensure that PUT requests apply to the most recent version of the reflection.

Example ZpzGgxw2l04=

Date and time that the reflection was created, in UTC format.

Example 2022-07-05T19:19:40.244Z

Date and time that the reflection was last updated, in UTC format.

Example 2023-01-10T17:12:40.244Z

Unique identifier for the anchor dataset that is associated with the reflection.

Example df99ab32-c2d4-4d1c-9e91-2c8be861bb8a

Data size of the latest reflection job (if one exists), in bytes.

Example 18639885

Data size of all reflection jobs that have not been pruned (if any exist), in bytes.

Example 142639924

If the reflection is available for accelerating queries, true. Otherwise, false.

Example true

If Dremio converts data from the reflection's Parquet files to Apache Arrow format when copying that data to executor nodes, true. Otherwise, false.

Example false

Information about the status of the reflection.

Example { "config": "OK", "refresh": "SCHEDULED", "availability": "AVAILABLE", "combinedStatus": "CAN_ACCELERATE", "failureCount": 0, "lastDataFetch": "2023-01-10T17:12:40.244Z", "expiresAt": "3022-07-05T19:19:40.244Z" }

Information about the fields displayed from the anchor dataset. Each displayFields object contains one attribute: name. Valid only for raw reflections.

Example [ { "name": "pickup_datetime" }, { "name": "passenger_count" }, { "name": "trip_distance_mi" }, { "name": "fare_amount" }, { "name": "tip_amount" }, { "name": "total_amount" } ]

Information about the dimension fields from the anchor dataset used in the reflection. Dimension fields are the fields you expect to group by when analyzing data. Each dimensionFields object contains two attributes: name and granularity. Valid only for aggregation reflections.

Example [ { "name": "pickup_date", "granularity": "DATE" }, { "name": "pickup_datetime", "granularity": "DATE" }, { "name": "dropoff_date", "granularity": "DATE" }, { "name": "dropoff_datetime", "granularity": "DATE" }, { "name": "passenger_count", "granularity": "DATE" }, { "name": "total_amount", "granularity": "DATE" } ]

Information about the measure fields from the anchor dataset used in the reflection. Measure fields are the fields you expect to use for calculations when analyzing the data. Each measureFields object contains two attributes: name and measureTypeList. Valid only for aggregation reflections.

Example [ { "name": "passenger_count", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "trip_distance_mi", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "fare_amount", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "surcharge", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "tip_amount", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "total_amount", "measureTypeList": [ "SUM", "COUNT" ] } ]

Information about the distribution fields from the anchor dataset used in the reflection. Distribution fields allow data from multiple datasets to be co-located and co-partitioned across nodes to minimize data movement during join operations. Each distributionFields object contains one attribute: name.

Example [ { "name": "trip_distance_mi" }, { "name": "total_amount" } ]

Information about the fields from the anchor dataset used to partition data in the reflection. Each field name is listed as an individual object. For more information, read Horizontally Partition Reflections that Have Many Rows.

Example [ { "name": "dropoff_date" }, { "name": "passenger_count" } ]

Information about the fields from the anchor dataset used for sorting in the reflection. Each sortFields object contains one attribute: name. For more information, read Sort Reflections on High-Cardinality Fields.

Example [ { "name": "trip_distance_mi" } ]

Method used to optimize data compression when executing reflections. CONSOLIDATED means Dremio minimizes the number of files produced. The query threads pool the data and ensure that the fewest number of files are written to the reflection store. Optimizing for a smaller number of files generally improves read performance because users can perform fewer searches for a given query. STRIPED means Dremio minimizes the time required to refresh the reflection. Each final-stage query thread opens its own writers to write the data, which can result in many small files if each query thread contains a small amount of data.

Enum CONSOLIDATED , STRIPED

Example CONSOLIDATED

If you can view reflections on all datasets of a source, system, space, or folder, true. Otherwise, false.

Example true

If you can create, edit, and view reflections on all datasets of a source, system, space, or folder, true. Otherwise, false.

Example true

Type of entity. For reflection objects, the entityType is reflection.

Example reflection

Status of the reflection configuration. If OK, the reflection configuration is free of errors. If INVALID, the reflection configuration contains one or more errors.

Enum OK , INVALID

Example OK

Status of the reflection refresh.

GIVEN_UP: Dremio attempted to refresh the reflection multiple times, but each attempt has failed and Dremio will not make further attempts.
MANUAL: Refresh period is set to 0, so you must use the Dremio UI to manually refresh the reflection.
RUNNING: Dremio is currently refreshing the reflection.
SCHEDULED: The reflection refreshes according to a schedule.

Enum GIVEN_UP , MANUAL , RUNNING , SCHEDULED

Example SCHEDULED

Status of the reflection's availability for accelerating queries.

Enum NONE , INCOMPLETE , EXPIRED , AVAILABLE

Example AVAILABLE

Status of the reflection based on a combination of config, refresh, and availability statuses.

CAN_ACCELERATE: The reflection is fully functional.
CAN_ACCELERATE_WITH_FAILURES: The most recent refresh failed to obtain a status, but Dremio still has a valid materialization.
CANNOT_ACCELERATE_MANUAL: The reflection is unable to accelerate any queries, and the Never Refresh option is selected for the refresh policy.
CANNOT_ACCELERATE_SCHEDULED: The reflection is currently unable to accelerate any queries, but it has been scheduled for a refresh at a future time.
DISABLED: The reflection has been manually disabled.
EXPIRED: The reflection has expired and cannot be used.
FAILED: The attempt to refresh the reflection has failed, typically three times in a row. The reflection is still usable.
INCOMPLETE: One or more pseudo-distributed file system (PDFS) nodes that contain materialized files are down (PDFS is supported for v21 and earlier). Only partial data is available. Configurations that use the Hadoop Distributed File System (HDFS) to store reflections should not experience incomplete status.
INVALID: The reflection is invalid because the underlying dataset has changed.
REFRESHING: The reflection is currently being refreshed.

Example CAN_ACCELERATE

Number of times that an attempt to refresh the reflection failed.

Example 0

Date and time that the reflection data was last refreshed, in UTC format. If the reflection is running, failing, or disabled, the lastDataFetch value is 1969-12-31T23:59:59.999Z.

Example 2023-01-10T17:12:40.244Z

Date and time that the reflection will expire, in UTC format. If the reflection is running, failing, or disabled, the lastDataFetch value is 1969-12-31T23:59:59.999Z.

Example 3022-07-05T19:19:40.244Z

Name of the field from the anchor dataset that is displayed in the raw reflection.

Example passenger_count

Name of the field from the anchor dataset that is configured as a dimension for the reflection.

Example pickup_date

Grouping used for the dimension field. When timestamp and date fields are configured as dimensions, Dremio can automatically extract and use the day-level date value (DATE) or use the field's original value (NORMAL).

Enum DATE , NORMAL

Example DATE

Name of the field from the anchor dataset that is configured as a measure for the reflection.

Example passenger_count

Types of calculations for which Dremio uses the specified measure field.

Enum APPROX_COUNT_DISTINCT , MIN , MAX , UNKNOWN , SUM , COUNT

Example [ "SUM", "COUNT" ]

Name of the field from the anchor dataset that is used for co-locating and co-partitioning data from multiple datasets across nodes.

Example trip_distance_mi

Name of the field from the anchor dataset on which you can partition the rows in the reflection.

Example trip_distance_mi

Name of the field from the anchor dataset that is used for sorting in the reflection.

Example dropoff_date

Reflection type. For more information, read Types of Reflections.

Enum RAW , AGGREGATION

Example AGGREGATION

Name to use for the reflection.

Example New Aggregation Reflection

Unique identifier for the anchor dataset to associate with the reflection.

Example df99ab32-c2d4-4d1c-9e91-2c8be861bb8a

If the reflection should be available for accelerating queries, true. Otherwise, false.

Example true

If Dremio should convert data from the reflection's Parquet files to Apache Arrow format when copying that data to executor nodes, true. Otherwise, false (default).

Example false

Information about the fields to display from the anchor dataset. The displayfields array must list every field in the anchor dataset or the reflection will fail. Each displayFields object contains one attribute: name. Valid only for raw reflections.

Example [ { "name": "pickup_datetime" }, { "name": "passenger_count" }, { "name": "trip_distance_mi" }, { "name": "fare_amount" }, { "name": "tip_amount" }, { "name": "total_amount" } ]

Information about the dimension fields from the anchor dataset to use in the reflection. Dimension fields are the fields you expect to group by when analyzing data. Each dimensionFields object contains two attributes: name and granularity. Valid only for aggregation reflections.

Example [ { "name": "pickup_datetime", "granularity": "DATE" }, { "name": "passenger_count", "granularity": "DATE" }, { "name": "total_amount", "granularity": "DATE" }, { "name": "trip_distance_mi", "granularity": "DATE" } ]

Information about the measure fields from the anchor dataset to use in the reflection. Measure fields are the fields you expect to use for calculations when analyzing the data. Each measureFields object contains two attributes: name and measureTypeList. Valid only for aggregation reflections.

Example [ { "name": "passenger_count", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "trip_distance_mi", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "fare_amount", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "tip_amount", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "total_amount", "measureTypeList": [ "SUM", "COUNT" ] } ]

Information about the distribution fields from the anchor dataset to use for co-locating and co-partitioning data from multiple datasets across nodes. Each distributionFields object contains one attribute: name.

Example [ { "name": "trip_distance_mi" }, { "name": "total_amount" } ]

Information about the fields from the anchor dataset to use to partition data in the reflection. Each field name is listed as an individual object. For more information, read Horizontally Partition Reflections that Have Many Rows.

Example [ { "name": "pickup_datetime" }, { "name": "passenger_count" } ]

Information about the fields from the anchor dataset to use for sorting in the reflection. Each sortFields object contains one attribute: name. For more information, read Sort Reflections on High-Cardinality Fields.

Example [ { "name": "trip_distance_mi" } ]

Method to use to optimize data compression when executing reflections. If CONSOLIDATED (default), Dremio will minimize the number of files produced. If STRIPED, Dremio will minimize the time required to refresh the reflection.

Enum CONSOLIDATED , STRIPED

Example CONSOLIDATED

To view reflections on all datasets of a source, system, space, or folder, true (default). Otherwise, false.

Example true

To create, edit, and view reflections on all datasets of a source, system, space, or folder, true (default). Otherwise, false.

Example true

Type of entity. For reflection objects, the entityType is reflection.

Name of the field to display from the anchor dataset.

Example { "name": "pickup_datetime" }

Name of the field from the anchor dataset to configure as a dimension for the reflection.

Example "name": "pickup_datetime"

Grouping to use for the dimension field. If Dremio should automatically extract the day-level date value and use it as the grouping value in the reflection, DATE. If Dremio should use the original value for grouping, NORMAL.

Enum DATE , NORMAL

Example "granularity": "DATE"

Name of the field from the anchor dataset that you expect to use in calculations. Fields of types LIST, MAP, and UNION are not valid measureFields.

Example "name": "passenger_count"

Types of calculations for which Dremio should use the specified measure field. The calculations must be valid for the specified field (for example, SUM is not valid for a timestamp field like pickup_datetime).

Enum APPROX_COUNT_DISTINCT , MIN , MAX , UNKNOWN , SUM , COUNT

Example [ "SUM", "COUNT" ]

Name of the field from the anchor dataset to use for co-locating and co-partitioning data from multiple datasets across nodes. In aggregation reflections, every field listed as a distribution field must also be listed as a dimension field.

Example { "name": "trip_distance_mi" }

Name of the field from the anchor dataset on which you want to be able to partition rows. Every field listed as a partition field must also be listed as a dimension field. If you list a field as a partition field, you cannot list the same field as a sort field in the same reflection.

Example { "name": "pickup_datetime" }

Name of the field from the anchor dataset to use for sorting in the reflection. Every field listed as a sort field must also be listed as a dimension field. If you list a field as a sort field, you cannot list the same field as a partition field in the same reflection.

Example { "name": "trip_distance_mi" }

Unique identifier for the reflection that you want to retrieve.

Example 95dda9dd-2371-467f-b68d-fc4c5ea57a8b

Unique identifier for the dataset whose reflections you want to retrieve.

Example 1df71752-69b7-47d9-9e6c-990e6b194aa4

Unique identifier for the reflection that you want to update.

Example 836eae91-306e-487b-a687-31c999653a86

Reflection type. For more information, read Types of Reflections.

Enum RAW , AGGREGATION

Example AGGREGATION

Name to use for the reflection.

Example New Aggregation Reflection

Unique identifier for the most recent version of the reflection. Dremio uses the tag value to ensure that you are updating the most recent version of the reflection.

Example ZpzGgxw2l04=

Unique identifier for the anchor dataset associated with the reflection.

Example gc870df7-ddf7-4d1e-bb9e-beef28ae773f

If the reflection should be available for accelerating queries, true. Otherwise, false.

Example false

If Dremio should convert data from the reflection's Parquet files to Apache Arrow format when copying that data to executor nodes, true. Otherwise, false (default).

Example true

Information about the dimension fields from the anchor dataset to use in the reflection. Dimension fields are the fields you expect to group by when analyzing data. Each dimensionFields object contains two attributes: name and granularity. Valid only for aggregation reflections.
If you omit the dimensionFields object in a PUT request, Dremio will remove all existing dimension fields from the reflection. To keep existing dimension fields while making other updates, duplicate the existing dimensionFields array in the PUT request.

Example [ { "name": "pickup_datetime", "granularity": "DATE" }, { "name": "passenger_count", "granularity": "DATE" }, { "name": "total_amount", "granularity": "DATE" }, { "name": "trip_distance_mi", "granularity": "DATE" } ]

Information about the fields to display from the anchor dataset. The displayfields array must list every field in the anchor dataset or the reflection will fail. Each displayFields object contains one attribute: name. Valid only for raw reflections.

Example [ { "name": "pickup_datetime" }, { "name": "passenger_count" }, { "name": "trip_distance_mi" }, { "name": "fare_amount" }, { "name": "tip_amount" }, { "name": "total_amount" } ]

Information about the measure fields from the anchor dataset to use in the reflection. Measure fields are the fields you expect to use for calculations when analyzing the data. Each measureFields object contains two attributes: name and measureTypeList. Valid only for aggregation reflections.
If you omit the measureFields object in a PUT request, Dremio will remove all existing measure fields from the reflection. To keep existing measure fields while making other updates, duplicate the existing measureFields array in the PUT request.

Example [ { "name": "passenger_count", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "trip_distance_mi", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "fare_amount", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "tip_amount", "measureTypeList": [ "SUM", "COUNT" ] }, { "name": "total_amount", "measureTypeList": [ "SUM", "COUNT" ] } ]

Information about the distribution fields from the anchor dataset to use for co-locating and co-partitioning data from multiple datasets across nodes. Each distributionFields object contains one attribute: name.
If you omit the distributionFields object in a PUT request, Dremio will remove all existing distribution fields from the reflection. To keep existing distribution fields while making other updates, duplicate the existing distributionFields array in the PUT request.

Example [ { "name": "trip_distance_mi" }, { "name": "total_amount" } ]

Information about the fields from the anchor dataset to use to partition data in the reflection. Each field name is listed as an individual object. If you omit the partitionFields object in a PUT request, Dremio will remove all existing partition fields from the reflection. To keep existing partition fields while making other updates, duplicate the existing partitionFields array in the PUT request. For more information, read Horizontally Partition Reflections that Have Many Rows.

Example [ { "name": "pickup_datetime" }, { "name": "passenger_count" } ]

Information about the fields from the anchor dataset to use for sorting in the reflection. Each sortFields object contains one attribute: name. If you omit the sortFields object in a PUT request, Dremio will remove all existing sort fields from the reflection. To keep existing sort fields while making other updates, duplicate the existing sortFields array in the PUT request. For more information, read Sort Reflections on High-Cardinality Fields.

Example [ { "name": "trip_distance_mi" } ]

Method to use to optimize data compression when executing reflections. If CONSOLIDATED (default), Dremio will minimize the number of files produced. If STRIPED, Dremio will minimize the time required to refresh the reflection.

Enum CONSOLIDATED , STRIPED

Example CONSOLIDATED

Name of the field from the anchor dataset to configure as a dimension for the reflection.

Example "name": "pickup_datetime"

Grouping to use for the dimension field. If Dremio should automatically extract the day-level date value and use it as the grouping value in the reflection, DATE. If Dremio should use the original value for grouping, NORMAL.

Enum DATE , NORMAL

Example "granularity": "DATE"

Name of the field to display from the anchor dataset.

Example { "name": "pickup_datetime" }

Name of the field from the anchor dataset that you expect to use in calculations. Fields of types LIST, MAP, and UNION are not valid measureFields.

Example "name": "passenger_count"

Types of calculations for which Dremio should use the specified measure field. The calculations must be valid for the specified field (for example, SUM is not valid for a timestamp field like pickup_datetime).

Enum APPROX_COUNT_DISTINCT , MIN , MAX , UNKNOWN , SUM , COUNT

Example [ "COUNT", "SUM" ]

Name of the field from the anchor dataset to use for co-locating and co-partitioning data from multiple datasets across nodes. Every field listed as a distribution field must also be listed as a dimension field.

Example { "name": "pickup_datetime" }

Name of the field from the anchor dataset on which you want to be able to partition rows. Every field listed as a partition field must also be listed as a dimension field. If you list a field as a partition field, you cannot list the same field as a sort field in the same reflection.

Example { "name": "dropoff_date" }

Name of the field from the anchor dataset to use for sorting in the reflection. Every field listed as a sort field must also be listed as a dimension field. If you list a field as a sort field, you cannot list the same field as a partition field in the same reflection.

Example { "name": "pickup_datetime" }

Unique identifier for the reflection that you want to delete.

Example 95dda9dd-2371-467f-b68d-fc4c5ea57a8b