# SYSTEMPREEMPTIVELOADCANDIDATES: Data Dictionary System pre-emptive load candidates The tables which this session may fetch before they are asked for, with who advised each one, how it is weighed and how many rows of it are wanted. One row per table; how far the fetching got is per partition, in SystemPreemptiveLoadingPartitions. Live session state rather than a log: the list is gone when the session ends. - Catalog: `DataDictionary` - Schema: `Invantive` - Alias: `plc` - Label: System pre-emptive load candidates This is a read-only view. The Data Dictionary API may not support changing the data or the Invantive UniversalSQL driver for Data Dictionary does not cover it. In the latter case, please use the table NativePlatformScalarRequests to upload data to the Data Dictionary API. ## View Columns The columns of the view `SYSTEMPREEMPTIVELOADCANDIDATES` are shown below. Each column has an SQL data type. | Name | Data Type | Label | Required | Documentation | |---|:---:|---|:---:|---| | `ADVISOR_CONTEXT` | `varchar2(240)` | Advised By Context | ☐ | Who gave the hint, where a hint advised it. | | `ADVISOR` | `varchar2(32)` | Advised By | ☑ | Who advised it: 'DriverDefault' for the driver of the platform, 'Hint' for something which announced it, and 'Journal' for the earlier questions of this user. | | `CATALOG_NAME` | `varchar2(240)` | Catalog | ☐ | Catalog of the object. | | `DATA_CONTAINER_ALIAS` | `varchar2(240)` | Data Container Alias | ☐ | Alias of the data container whose driver proposed it. | | `ESTIMATED_NUMBER_OF_CALLS` | `int64` | Estimated Number Of Calls | ☐ | Number of calls one fetch is expected to take, or empty when the driver cannot tell. | | `ESTIMATED_NUMBER_OF_ROWS` | `int64` | Estimated Number Of Rows | ☐ | Number of rows the platform is expected to hold, as far as the driver knows. | | `FRESHNESS_AGE_SEC` | `double` | Freshness Age | ☑ | Age in seconds below which what is already cached makes a fetch pointless. | | `ID` | `int64` | Candidate | ☑ | Identity of the candidate within the session, by which the progress per partition refers back to it. | | `INCLUDE_ON_FIRST_USE` | `boolean` | Include On First Use | ☑ | Whether a session with no history of earlier questions fetches this one. | | `INTEREST_UNTIL_DATE_UTC` | `datetime` | Interest Until Date | ☐ | Moment until which it is expected to be asked for (UTC), or empty when the expectation is open-ended. | | `KIND` | `varchar2(32)` | Kind | ☑ | What has to be done to fetch it: 'IncrementalRefresh', 'PageSet', 'Blobs' or 'Metadata'. | | `MAXIMUM_NUMBER_OF_ROWS` | `int64` | Maximum Number Of Rows | ☐ | Number of rows to fetch, or empty for the whole set. | | `PARTITION_SCOPE` | `varchar2(32)` | Partition Scope | ☑ | Which partitions it covers: 'One', 'Selected' or 'All'. | | `PRIORITY` | `varchar2(32)` | Priority | ☑ | How much of a low allowance it may be given: 'Always', 'Normal' or 'Spare'. | | `SCHEMA_NAME` | `varchar2(240)` | Schema | ☐ | Schema of the object. | | `SCORE_FROM_HINT` | `double` | Score From Announcement | ☑ | Part of the score which comes from an announcement that it will be asked for. | | `SCORE_FROM_JOURNAL` | `double` | Score From History | ☑ | Part of the score which comes from the earlier questions of this user at this time of day. | | `SCORE_FROM_PRIOR` | `double` | Score From Expectation | ☑ | Part of the score which comes from what the driver expects of this object. | | `SCORE` | `double` | Score | ☑ | Calls expected to be saved per call spent, by which candidates are ordered within their priority. | | `TABLE_NAME` | `varchar2(240)` | Table | ☑ | Name of the table, table function or view. |