Change the index type for a column

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Overview

Explains what the feature is or what its benefits are to the user or customer.

Feature

ThoughtSpot indexes column names and unique column values. The indexes are used to dynamically generate suggestions in the search bar when typing a search.

You can change the way a column is indexed by modifying its Index value in the modeling file, to influence the suggestions that will appear for that column. The default behavior of indexing is as follows:

All column names are indexed using their ColumnName value.
Values for columns with the column type of MEASURE are not indexed.
Values for columns with the data type of DATE are not indexed.
Columns that contain a large amount of free-form text (i.e. the number of characters in more than a few of the fields is more than 50) are indexed as PREFIX_ONLY by default.
Short strings (like a firstname column) are indexed using PREFIX_AND_SUBSTRING by default, which indexes both prefix and substrings.

It is not recommended to change the indexing for columns with very large free text values. These should not to be indexed, because indexing on these values is not useful and may generate confusing suggestions.

You can override the default behavior by editing the modeling file to change the Index value for any columns that should be indexed differently. There are several different supported index types:

Table 1. Supported index types
Index type	Description
DEFAULT	This is the default value. The default indexing behavior will apply to the column values, depending on their type. PREFIX_AND SUBSTRING for short values and PREFIX_ONLY for long values and free-form text.
DONT_INDEX	Prevents indexing on the column values.
PREFIX_AND_SUBSTRING	Allows full indexing such that prefix and sub-string search both work for the column values.
PREFIX_ONLY	Allows indexing such that only prefix search works for the column values.
PREFIX_AND_WORD_SUBSTRING	Allows indexing such that only prefix search works for each word of a multi-word string, for the column values.

Find the column whose index type you want to modify, and set its Index Type.
If you are using the model file, double click in the Index cell, and type in the index type you want to use.
Save your changes.

Consider a column in which there are four values “ThoughtSpot”, “Thought”, “Spot” and “Thought Spot”. If you search for “sp”, depending on the setting for indexing, the column value search result suggestions will vary:

Table 2. Example of the effects of indexing on search bar suggestions
Index field value	Search bar suggestions
DEFAULT	“ThoughtSpot”, “Spot” and “Thought Spot”
DONT_INDEX	No suggestions.
PREFIX_AND_SUBSTRING	“ThoughtSpot”, “Spot” and “Thought Spot”
PREFIX_ONLY	“Spot”
PREFIX_AND_WORD_SUBSTRING	“Spot” and “Thought Spot”