Columns

Use this reference to learn about the metadata available for Firebolt columns using the information schema.

You can use the information_schema.columns view to return information about all columns in a table in a database. The view is available in each database and contains one row for each column. You can use a SELECT query to return information about each column as shown in the example below.

To view column information, the user must have USAGE privileges on both the schema and the database, as well as any necessary table-level privileges or ownership of the table.

SELECT
  *
FROM
  information_schema.columns;

Columns in information_schema.columns

Each row has the following columns with information about each column.

Column Name	Data Type	Description
table_catalog	TEXT	Name of the catalog. Firebolt provides a single default catalog.
table_schema	TEXT	Name of the database containing the table.
table_name	TEXT	Name of the table containing the column.
column_name	TEXT	Name of the column.
ordinal_position	BIGINT	The ordinal position of the column.
column_default	TEXT	The default expression for the column, if it exists.
is_nullable	TEXT	YES if the column may contain NULL, NO otherwise.
data_type	TEXT	The data type of the column.
compression	TEXT	The compression codec(s) applied to the column. Shows the full compression chain if multiple codecs are used (e.g., delta, zstd(3)).
is_in_partition_expr	TEXT	YES if the column is included in the table’s PARTITION BY clause, NO otherwise.
is_in_primary_index	TEXT	YES if the column is included in the table’s PRIMARY INDEX clause, NO otherwise.
numeric_precision	BIGINT	The numeric precision. For numeric columns only.
description	TEXT	The description of the column.
character_maximum_length	NULL	Not applicable for Firebolt.
character_octet_length	NULL	Not applicable for Firebolt.
numeric_precision_radix	NULL	Not applicable for Firebolt.
interval_type	NULL	Not applicable for Firebolt.
interval_precision	NULL	Not applicable for Firebolt.
character_set_catalog	NULL	Not applicable for Firebolt.
character_set_schema	NULL	Not applicable for Firebolt.
character_set_name	NULL	Not applicable for Firebolt.
collation_catalog	NULL	Not applicable for Firebolt.
collation_schema	NULL	Not applicable for Firebolt.
collation_name	NULL	Not applicable for Firebolt.
domain_catalog	NULL	Not applicable for Firebolt.
domain_schema	NULL	Not applicable for Firebolt.
domain_name	NULL	Not applicable for Firebolt.
udt_catalog	NULL	Not applicable for Firebolt.
udt_schema	NULL	Not applicable for Firebolt.
udt_name	NULL	Not applicable for Firebolt.
scope_catalog	NULL	Not applicable for Firebolt.
scope_schema	NULL	Not applicable for Firebolt.
scope_name	NULL	Not applicable for Firebolt.
maximum_cardinality	NULL	Not applicable for Firebolt.
dtd_identifier	NULL	Not applicable for Firebolt.
is_self_referencing	NULL	Not applicable for Firebolt.
is_identity	NULL	Not applicable for Firebolt.
identity_generation	NULL	Not applicable for Firebolt.
identity_start	NULL	Not applicable for Firebolt.
identity_increment	NULL	Not applicable for Firebolt.
identity_maximum	NULL	Not applicable for Firebolt.
identity_minimum	NULL	Not applicable for Firebolt.
identity_cycle	NULL	Not applicable for Firebolt.
is_generated	NULL	Not applicable for Firebolt.
generation_expression	NULL	Not applicable for Firebolt.
is_updatable	NULL	Not applicable for Firebolt.

Example: Viewing compression settings

To view compression settings for columns in a specific table:

SELECT 
    column_name,
    data_type,
    compression,
    is_nullable
FROM information_schema.columns 
WHERE table_name = 'my_table'
ORDER BY ordinal_position;

Example output:

column_name    | data_type         | compression        | is_nullable
---------------|-------------------|--------------------|-----------
id             | INTEGER           | lz4                | NO
sensor_id      | INTEGER           | delta, lz4         | NO  
temperature    | DOUBLE PRECISION  | gorilla, zstd(3)   | YES
timestamp      | TIMESTAMPTZ       | doubledelta, lz4   | NO
metadata       | TEXT              | zstd(15)           | YES