Purpose
Use this statement to print column information for a given table or view.
Prerequisites
- 
                                                                    You need either the system privilege USE ANY SCHEMAor the object privilegeUSAGEon the target schema, or the schema must be owned by you or one of your assigned roles.
- If the object to be described is a table, one of the following conditions must be fulfilled:
- The current user has one of the following system privileges: SELECT ANY TABLE(orSELECT ANY DICTIONARYin context of system tables, respectively),INSERT ANY TABLE,UPDATE ANY TABLE,DELETE ANY TABLE,ALTER ANY TABLEorDROP ANY TABLE.
- The current user has any object privilege on the table.
- The table belongs to the current user or one of their roles.
 
- The current user has one of the following system privileges: 
- If the object to be described is a view, one of the following conditions must be fulfilled:
- The current user has one of the following system privileges: SELECT ANY TABLEorDROP ANY VIEW.
- The current user has any object privilege on the view.
- The view belongs to the current user or one of their roles.
 
- The current user has one of the following system privileges: 
Syntax
describe::=
                                                                         
                                                                    
Usage notes
- The SQL_TYPEcolumn shows the data type. In case of a string type, the used character set (ASCII or UTF-8) is also shown.
- The NULLABLEcolumn indicates whether the column is permitted to contain NULL values.
- The value of columns DISTRIBUTION_KEYandPARTITION_KEYshow whether the column is part of the distribution and partition keys (for additional information, see ALTER TABLE (Distribution/Partitioning)). For views these values are always NULL.
- If you specify the option FULLthe additional columnCOLUMN_COMMENTshows the column comment (cut to maximum 200 characters), provided that this was set either implicitly by the CREATE TABLE or CREATE VIEW command or explicitly by the COMMENT statement.
- DESCRIBEcan be abbreviated as- DESC. For example:- DESC my_table;.
Example:
CREATE TABLE t (i DECIMAL COMMENT IS 'id column',
         d DECIMAL(20,5),
         j DATE,
         k VARCHAR(5),
         DISTRIBUTE BY i,
         PARTITION BY d);
         
DESCRIBE t;Result:
| COLUMN_NAME | SQL_TYPE | NULLABLE | DISTRIBUTION_KEY | PARTITION_KEY | 
|---|---|---|---|---|
| I | DECIMAL(18,0) | TRUE | TRUE | FALSE | 
| D | DECIMAL(20,5) | TRUE | FALSE | TRUE | 
| J | DATE | TRUE | FALSE | FALSE | 
| K | VARCHAR(5) UTF-8 | TRUE | FALSE | FALSE |