MENJELASKAN SKEMA

  • Artikel

Berlaku untuk:centang ditandai ya pemeriksaan Databricks SQL ditandai ya Databricks Runtime

Mengembalikan metadata dari skema yang ada. Informasi metadata mencakup nama, komentar, dan lokasi skema pada sistem file. Jika opsi opsional EXTENDED ditentukan, properti skema juga dikembalikan.

Meskipun penggunaan SCHEMA dan DATABASE dapat dipertukarkan, SCHEMA lebih disukai.

Sintaks

{ DESC | DESCRIBE } SCHEMA [ EXTENDED ] schema_name

Parameter

  • schema_name: Nama skema (skema) yang ada dalam sistem. Jika nama tidak ada, pengecualian akan dilemparkan.

Contoh

-- Create employees SCHEMA
> CREATE SCHEMA employees COMMENT 'For software companies';

-- Describe employees SCHEMA.
-- Returns Database Name, Description and Root location of the filesystem
-- for the employees SCHEMA.
> DESCRIBE SCHEMA employees;
 database_description_item    database_description_value
 ------------------------- -----------------------------
             Database Name                     employees
               Description        For software companies
                  Location file:/you/Temp/employees.db

-- Create employees SCHEMA
> CREATE SCHEMA employees COMMENT 'For software companies';

-- Alter employees schema to set DBPROPERTIES
> ALTER SCHEMA employees SET DBPROPERTIES ('Create-by' = 'Kevin', 'Create-date' = '09/01/2019');

-- Describe employees SCHEMA with EXTENDED option to return additional schema properties
> DESCRIBE SCHEMA EXTENDED employees;
 database_description_item                    database_description_value
 ------------------------- ---------------------------------------------
             Database Name                                     employees
               Description                        For software companies
                  Location                 file:/you/Temp/employees.db
                Properties ((Create-by,kevin), (Create-date,09/01/2019))

-- Create deployment SCHEMA
> CREATE SCHEMA deployment COMMENT 'Deployment environment';

-- Describe deployment.
> DESCRIBE SCHEMA deployment;
 database_description_item database_description_value
 ------------------------- ------------------------------
             Database Name                     deployment
               Description         Deployment environment
                  Location file:/you/Temp/deployment.db