Terminology in EXPLAIN Text for the Object File System - Teradata VantageCloud Lake

Lake - Working with SQL

Deployment
VantageCloud
Edition
Lake
Product
Teradata VantageCloud Lake
Release Number
Published
February 2025
ft:locale
en-US
ft:lastEdition
2025-11-21
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jbe1714339405530.ditamap
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jbe1714339405530
Phrase Explanation
root metadata of ...
  When reading an Object File System table, this step is reading the Root Index/Root Metadata to get the Leaf information. Reading the Root Metadata is followed by reading the Leaf Index of an Object File System table. See also "leaf metadata of …".
leaf metadata of ...
  When reading an Object File System table, this step is reading the Leaf Index/Leaf Metadata to get the Data Object information. Reading the Leaf Metadata is done after reading the Root Index/Root Metadata of an Object File System table and is followed by reading the Data Objects. See also "root metadata of …".
delete root metadata of ...
  The to-be-deleted object information is stored in the Delete Root Metadata. Objects in the Delete Root Metadata are physically deleted at a later stage during a clearing operation.
and deleted objects are inserted into DEL root object (Verbose Explain)
  Appears in the Verbose Explain of a full table delete on an Object File System table, saying that the root to be deleted will be put in the Delete Root Object, which is physically deleted later.
Index rows for the rebuilt objects go into …
  Appears in a DML step, telling the user that the index information corresponding to the rebuilt objects will be placed in the specified spool. This happens in a delete or merge delete step where rows qualify the given condition and a need to rebuild an object arises.
and rows for delete object maintenance go into ...
  The index rows in a delete or merge delete step that corresponds to the to-be deleted objects are placed in the specified spool.
and index rows go into ...
  The index row information after a merge into Object File System Table/Leaf Metadata of Object File System Table/Root Metadata of an Object File System table is put in the specified spool.
by way of external metadata in Spool …
  When reading an Object File System table, this step is reading the Leaf Metadata or the table data using the metadata present in the specified keyspool number.
by way of an index scan …
  Only an index is accessed to retrieve the required information instead of doing an all-rows scan.
redistributed by value range of (..) ...
  Rows are redistributed based on the data value, which could be needed for sorting or other operations.
do a single-AMP insert into a journal …
  A Journaling Step that is done for DML operations – UPDATE, DELETE and INSERT on Object File System tables and also DROP tables.
spoil the parser's dictionary cache for the storage
  The storage information will be cleared from the dictionary cache.
LOB root metadata of…
  An operation is being done on the LOB root index of an Object File System table that has LOB columns.
LOB leaf metadata of …
  An operation is being done on the LOB leaf index of an Object File System table that has LOB columns.
and LOB index rows go into …
  A merge step into the LOB indexes, the rows are sent to the specified spool.