17.00 - Usage Notes - Teradata Database

Teradata Vantageā„¢ - Data Dictionary

prodname
Advanced SQL Engine
Teradata Database
vrm_release
17.00
created_date
June 2020
category
Administration
Programming Reference
featnum
B035-1092-170K

The ActionsV[X] views are security zone constrained views that contain recommended map actions, such as move a table to a new map. The mover procedure reads the actions from this table and schedules them for execution. Users can manually override actions in ActionsTbl, using SQL statements, such as UPDATE, DELETE, and INSERT.

When executing DML statements directly against ActionsTbl, users must include a WHERE condition on column ActionListName to limit the changes to a designated action list.

ActionsVX returns only the objects to which the user has access.

Inserting Rows in ActionsTbl

Each row inserted into ActionsTbl must specify a non-null value for the following columns which represent the required metadata for defining a map related action: Action, DatabaseName, TableName, DestinationMap, ActionListName, LastAlterTimeStamp, LastAlterUID, and Issues. These columns are automatically populated. The NOT NULL constraint defined for each of these columns ensures that manual INSERTs performed on this table populate these columns as well. Although it is recommended that manual UPDATEs performed on ActionsTbl update the LastAlterTimeStamp and LastAlterUID columns, the system does not enforce this.

ActionListName

Named list of actions of which this action is a member. See the related Advisor procedure parameter OutputActionList and see the Mover procedure.

FractionOfPermDBFree

The fraction of free permanent space the table takes in the database. ALTER TABLE MAP takes twice the space during the operation, and this value indicates the fraction of free space that will be used.

GroupOrder and ActionOrder

GroupOrder is a common identifier and priority rank of the group in which this action is a member. ActionOrder is a priority rank of an action within its group. These columns are applicable only for rows whose Action value is Alter.

When determining the priority execution order for Alter actions in ActionsTbl, values in column GroupOrder are compared to establish a ranking between groups and then ActionOrder column values are compared to establish a ranking within each group. Because they represent ranks, lower values have a higher priority. GroupOrder and ActionOrder values generated by the AnalyzeSP procedure are assigned consecutive positive integer values starting with 1. Users that wish to manually add a new group between existing ones can use the fractional value portion of the GroupOrder column. Similarly, users wishing to add new actions to an existing group can use the fractional portion of the ActionOrder column. When comparing two values for ordering, the fractional portion is only applicable when the integer portions are equal. In addition, only the digits in the fractional portion are considered when ranking; the decimal point has no bearing. A GroupOrder value of NULL designates the action is not part of any group and is assigned the lowest possible group ranking. An ActionOrder value of NULL designates the lowest possible ranking within its group. An action with NULL specified for both GroupOrder and ActionOrder is assigned the lowest possible ranking among all actions.

UDICnt

The number of rows updated, deleted, or inserted on this the table by logged SQL statements during the period analyzed. Indicator of the volatility for the table.

Possible Values for Action

Type of action to perform on the table.

Value Description
Alter Move existing table data to new destination map.

For example, use the ALTER statement to change the Action:

ALTER {TABLE | JOIN INDEX | HASH INDEX} <TableName>
MAP = <DestinationMap> [COLOCATE USING [<ColocateName>];
Exclude Do not perform any action on this table for the specified destination map.

Possible Values for Issues

Value Description
Y Y indicates there are issues with this action. For details about what the issues are, see the ActionsTblDescription column.
N N indicates there are no issues.

Possible Values for Issues and ActionsTblDescription

Issues Value ActionsTblDescription Value
N Table is considered to be empty, and is not allowed to be put in a sparse map.
N Table is in the exclusion list.
N Move table for system expansion.

The target map has more AMPs than the map the table is currently in.

N Destination map has less or the same number of AMPs as the source map.
N Table is very small. One-AMP sparse map is recommended.
N Small tables are optimized by moving to sparse map.
N Table is too big for a sparse map.
N Small tables may not be optimized in a contiguous map.
N Moving to bigger sparse map.
Y Moving to smaller sparse map.
Y Source and destination maps are the same.

A table is marked Exclude if the source and target maps are the same.

Y Journal will be invalidated after ALTER TABLE.
Y Join Index will be invalidated after ALTER TABLE.

One or more join indexes will be invalidated after the table is moved to a new map.

Y Hash Index will be invalidated after ALTER TABLE.

One or more hash indexes will be invalidated after the table is moved to a new map.

Y Not enough free perm space.

There is not enough free space to move the table to a new map.

Possible Values for Origin

Value Description
A A indicates that the Advisor procedures are the source of the action to perform.
U U or NULL indicates a user inserted this action (the source of the action is a user).