DESCRIBE STAGE¶
描述为暂存区中的属性指定的值(文件格式、副本和位置),以及每个属性的默认值。
DESCRIBE 可以缩写为 DESC。
语法¶
DESC[RIBE] STAGE <name>
参数¶
name
指定要描述的暂存区的标识符。如果标识符包含空格或特殊字符,则整个字符串必须放在双引号内。放在双引号内的标识符也区分大小写。
使用说明¶
若要对此命令的输出进行后处理,可以使用 RESULT_SCAN 函数,该函数会将输出视为可查询的表。
输出¶
命令输出在以下列中提供暂存区属性和元数据。
列 |
描述 |
---|---|
|
每个暂存区属性所属的父属性。可能的值包括 STAGE_FILE_FORMAT、STAGE_COPY_OPTIONS、STAGE_LOCATION、STAGE_CREDENTIALS 和 DIRECTORY。 |
|
属性的名称。有关属性说明,请参阅 CREATE STAGE。 |
|
属性类型。 |
|
分配给属性的值。 |
|
默认属性值。 |
备注
对于具有目录表的暂存区,输出包括名为 LAST_REFRESHED_ON 且类型为 TIMESTAMP 的属性。LAST_REFRESHED_ON 指示目录表的元数据上次手动或自动与暂存区上的关联文件同步的时间。
示例¶
描述一个名为 my_s3_stage
的内部暂存区:
DESC STAGE my_s3_stage; +--------------------+--------------------------------+---------------+-------------------------------------------------------+------------------+ | parent_property | property | property_type | property_value | property_default | |--------------------+--------------------------------+---------------+-------------------------------------------------------+------------------| | STAGE_FILE_FORMAT | TYPE | String | CSV | CSV | | STAGE_FILE_FORMAT | RECORD_DELIMITER | String | \n | \n | | STAGE_FILE_FORMAT | FIELD_DELIMITER | String | , | , | | STAGE_FILE_FORMAT | FILE_EXTENSION | String | | | | STAGE_FILE_FORMAT | SKIP_HEADER | Integer | 0 | 0 | | STAGE_FILE_FORMAT | DATE_FORMAT | String | AUTO | AUTO | | STAGE_FILE_FORMAT | TIME_FORMAT | String | AUTO | AUTO | | STAGE_FILE_FORMAT | TIMESTAMP_FORMAT | String | AUTO | AUTO | | STAGE_FILE_FORMAT | BINARY_FORMAT | String | HEX | HEX | | STAGE_FILE_FORMAT | ESCAPE | String | NONE | NONE | | STAGE_FILE_FORMAT | ESCAPE_UNENCLOSED_FIELD | String | \\ | \\ | | STAGE_FILE_FORMAT | TRIM_SPACE | Boolean | false | false | | STAGE_FILE_FORMAT | FIELD_OPTIONALLY_ENCLOSED_BY | String | NONE | NONE | | STAGE_FILE_FORMAT | NULL_IF | List | [\\N] | [\\N] | | STAGE_FILE_FORMAT | COMPRESSION | String | AUTO | AUTO | | STAGE_FILE_FORMAT | ERROR_ON_COLUMN_COUNT_MISMATCH | Boolean | true | true | | STAGE_FILE_FORMAT | VALIDATE_UTF8 | Boolean | true | true | | STAGE_FILE_FORMAT | SKIP_BLANK_LINES | Boolean | false | false | | STAGE_FILE_FORMAT | REPLACE_INVALID_CHARACTERS | Boolean | false | false | | STAGE_FILE_FORMAT | EMPTY_FIELD_AS_NULL | Boolean | true | true | | STAGE_FILE_FORMAT | SKIP_BYTE_ORDER_MARK | Boolean | true | true | | STAGE_FILE_FORMAT | ENCODING | String | UTF8 | UTF8 | | STAGE_COPY_OPTIONS | ON_ERROR | String | ABORT_STATEMENT | ABORT_STATEMENT | | STAGE_COPY_OPTIONS | SIZE_LIMIT | Long | | | | STAGE_COPY_OPTIONS | PURGE | Boolean | false | false | | STAGE_COPY_OPTIONS | RETURN_FAILED_ONLY | Boolean | false | false | | STAGE_COPY_OPTIONS | ENFORCE_LENGTH | Boolean | true | true | | STAGE_COPY_OPTIONS | TRUNCATECOLUMNS | Boolean | false | false | | STAGE_COPY_OPTIONS | FORCE | Boolean | false | false | | STAGE_LOCATION | URL | String | ["s3://EXAMPLE-S3-PATH/my-csvfiles/"] | | | STAGE_CREDENTIALS | AWS_KEY_ID | String | | | | DIRECTORY | LAST_REFRESHED_ON | Timestamp | 2023-05-03 12:50:28.000 -0700 | | | DIRECTORY | ENABLE | Boolean | true | false | | DIRECTORY | AUTO_REFRESH | Boolean | false | false | +--------------------+--------------------------------+---------------+-------------------------------------------------------+------------------+