call the DoMetaQuery operation to query objects that meet specified conditions and list object information by a specified field and sorting order-Object Storage Service(OSS)-阿里云帮助中心

The DoMetaQuery operation queries objects that meet specified conditions and lists object information by a specified field and sorting order. You can also nest Query elements for complex queries and use aggregate operations to collect statistics on field values.

Precautions

To query objects that meet specified conditions, you must have the oss:DoMetaQuery permission. Grant custom permissions to a RAM user.

Request syntax

Scalar retrieval

POST /?metaQuery&comp=query&mode=basic HTTP/1.1
Host: BucketName.oss-cn-hangzhou.aliyuncs.com
Date: GMT Date
Authorization: SignatureValue 
<?xml version="1.0" encoding="UTF-8"?>
<MetaQuery>
  <NextToken></NextToken>
  <MaxResults>5</MaxResults>
  <Query>{"Field": "Size","Value": "1048576","Operation": "gt"}</Query>
  <Sort>Size</Sort>
  <Order>asc</Order>
  <Aggregations>
    <Aggregation>
      <Field>Size</Field>
      <Operation>sum</Operation>
    </Aggregation>
    <Aggregation>
      <Field>Size</Field>
      <Operation>max</Operation>
    </Aggregation>
  </Aggregations>
</MetaQuery>

Vector retrieval

POST /?metaQuery&comp=query&mode=semantic HTTP/1.1
Host: BucketName.oss-cn-hangzhou.aliyuncs.com
Date: GMT Date
Authorization: SignatureValue 
<?xml version="1.0" encoding="UTF-8"?>
<MetaQuery>
  <MaxResults>99</MaxResults>
  <Query>An aerial view of a snow-covered forest</Query>
  <MediaTypes>
    <MediaType>image</MediaType>
  </MediaTypes>  
  <SimpleQuery>{"Operation":"gt", "Field": "Size", "Value": "30"}</SimpleQuery>
</MetaQuery>

Request headers

DescribeRegions uses only common request headers. For more information, see Common request headers.

Request elements

Scalar retrieval

Name	Type	Required	Example value	Description
mode	String	Yes	basic	Sets the retrieval mode to scalar retrieval.
MetaQuery	Container	Yes	N/A	The container for query conditions. Child nodes: NextToken, MaxResults, Query, Sort, Order, and Aggregations
NextToken	String	No	MTIzNDU2Nzg6aW1tdGVzdDpleGFtcGxlYnVja2V0OmRhdGFzZXQwMDE6b3NzOi8vZXhhbXBsZWJ1Y2tldC9zYW1wbGVvYmplY3QxLmpw****	The pagination token. Required when the total number of objects exceeds MaxResults. Object information is returned in lexicographical order starting from the object specified by NextToken. Leave this field empty for the first request. Parent node: MetaQuery
MaxResults	Integer	No	5	The maximum number of objects to return. Valid values: 0 to 100. Default: 100. Takes effect when unset or set to 0. Parent node: MetaQuery
Query	String	Yes	{"Field": "Size","Value": "1048576","Operation": "gt"}	The query condition. Options: Operation: The operator. Valid values: eq (equal to), gt (greater than), gte (greater than or equal to), lt (less than), lte (less than or equal to), match (fuzzy query), prefix (prefix query), and (logical AND), or (logical OR), and not (logical NOT). Field: The field name. Supported fields and operators are listed in Appendix: Fields and operators for scalar retrieval. Value: The field value. SubQueries: The subquery conditions. Options are the same as simple query conditions. Required only when Operation is a logical operator (and, or, or not). For examples of queries, see DoMetaQuery. Parent node: MetaQuery
Sort	String	No	Size	Sorts results by a specified field. Sortable fields are listed in Appendix: Fields and operators for scalar retrieval. Parent node: MetaQuery
Order	String	No	asc	The sorting order. Valid values: asc: ascending desc (default): descending Parent node: MetaQuery
Aggregations	Container	No	N/A	The container for aggregate operations. Child node: Aggregation Parent node: MetaQuery
Aggregation	Container	No	N/A	The container for a single aggregate operation. Child nodes: Field and Operation Parent node: Aggregations
Field	String	No	Size	The field name. Supported fields and operators are listed in Appendix: Fields and operators for scalar retrieval. Parent node: Aggregation
Operation	String	No	sum	The operator in the aggregate operation. Valid values: min: minimum value max: maximum value average: average value sum: sum Count distinct: deduplicated count group: group count Parent node: Aggregation

Vector retrieval

Name	Type	Required	Example	Description
mode	String	Yes	semantic	Sets the retrieval mode to vector retrieval.
MetaQuery	Container	Yes	N/A	The container for query conditions. Child nodes: MaxResults, Query, MediaTypes, and SimpleQuery
MaxResults	Integer	No	5	The maximum number of objects to return. Valid values: 0 to 100. Default: 100. Takes effect when unset or set to 0. Parent node: MetaQuery
Query	String	Yes	An aerial view of a snow-covered forest	The content to retrieve. Parent node: MetaQuery
MediaTypes	Container	Yes	N/A	The multimedia metadata retrieval conditions. Parent node: MetaQuery
MediaType	String	Yes	image	The type of multimedia to retrieve. Valid values: Image: video audio document Parent node: MediaTypes
SimpleQuery	String	No	{"Operation":"gt", "Field": "Size", "Value": "30"}	The query condition. Options: Operation: The operator. Valid values: eq (equal to), gt (greater than), gte (greater than or equal to), lt (less than), lte (less than or equal to), match (fuzzy query), prefix (prefix query), and (logical AND), or (logical OR), and not (logical NOT). Field: The field name. Supported fields and operators are listed in Appendix: Fields and operators for vector retrieval. Value: The field value. SubQueries: The subquery conditions. Options are the same as simple query conditions. Required only when Operation is a logical operator (and, or, or not). Parent node: MetaQuery

Response headers

The response contains only common response headers. For more information, see Common response headers.

Response elements

Scalar retrieval

Name	Type	Example	Description
MetaQuery	Container	N/A	The container for query results. Child nodes: NextToken, Files, and Aggregations
NextToken	String	MTIzNDU2Nzg6aW1tdGVzdDpleGFtcGxlYnVja2V0OmRhdGFzZXQwMDE6b3NzOi8vZXhhbXBsZWJ1Y2tldC9zYW1wbGVvYmplY3QxLmpw****	The pagination token. Required when the total number of objects exceeds MaxResults. Pass this value as NextToken in the next request to retrieve remaining results. Returned only when not all objects are included in the response. Parent node: MetaQuery
Files	Container	N/A	The container for object information. Child node: File Parent node: MetaQuery
File	Container	N/A	The container for a single object. Child nodes: Filename, Size, FileModifiedTime, OSSObjectType, OSSStorageClass, ObjectACL, ETag, OSSTaggingCount, OSSTagging, and OSSCRC64 Parent node: Files
Filename	String	exampleobject.txt	The full path of the object. Parent node: File
Size	Integer	120	The size of the object in bytes. Parent node: File
FileModifiedTime	String	2025-05-19T16:14:38+08:00	The last modified time of the object. The format is RFC3339Nano. Parent node: File
OSSObjectType	String	Normal	The type of the object. Valid values: Normal: The object is uploaded by calling the PutObject operation . Appendable: The object is uploaded by calling the AppendObject operation. Multipart: The object is uploaded by calling the MultipartUpload operation. Symlink: The symbolic link is created by calling the PutSymlink operation. Parent node: File
OSSStorageClass	String	Standard	The storage class of the object. Valid values: Standard: Highly reliable, highly available, high-performance storage for frequently accessed data. IA: Suitable for long-term storage with infrequent access (once or twice a month on average). Archive: Suitable for long-term archival of rarely accessed data (six months or more recommended). Requires approximately 1 minute to restore before reading. ColdArchive: Suitable for long-term storage of rarely accessed data. Parent node: File
ObjectACL	String	default	The ACL of the object. Valid values: default: Inherits the bucket ACL. private: Only the object owner and authorized users can read and write. Other users cannot access the object. public-read: The owner and authorized users can read and write. Other users can only read. Use with caution. public-read-write: All users can read and write. Use with caution. Parent node: File
ETag	String	"fba9dede5f27731c9771645a3986****"	An ETag is generated when an object is created. It identifies the content of the object. For an object created by a PutObject request, the ETag value is the MD5 hash of its content. For objects created by other methods, the ETag is a unique value but not the MD5 hash of the content. Note You can use the ETag to check whether object content has changed, but do not use it as the MD5 hash for data integrity verification. Parent node: File
OSSTaggingCount	Integer	2	The number of tags of the object. Parent node: File
OSSTagging	Container	N/A	The container for tag information. Child node: Tagging Parent node: File
Tagging	Container	N/A	The container for a single tag. Child nodes: Key and Value Parent node: OSSTagging
Key	String	owner	The key of the tag or user-defined metadata. The key of user-defined metadata must be prefixed with `x-oss-meta-`. Parent nodes: Tagging and UserMeta
Value	String	John	The value of the tag or user-defined metadata. Parent nodes: Tagging and UserMeta
OSSCRC64	String	4858A48BD1466884	The 64-bit CRC value of the object. The 64-bit CRC value is calculated based on the CRC-64/XZ standard. Parent node: File
Aggregations	Container	N/A	The container for aggregate operations. Child nodes: Field, Operation, Operation, Value, and Groups Parent node: MetaQuery
Field	String	Size	The field name. Parent node: Aggregations
Operation	String	sum	The aggregate operator. Parent node: Aggregations
Value	Floating-point number	200	The result value of the aggregate operation. Parent node: Aggregations
Groups	Container	N/A	The list of grouping and aggregation results. Child nodes: Value and Count Parent node: Aggregations
Value	String	100	The value of the grouping and aggregation. Parent node: Groups
Count	Integer	5	The count of grouping and aggregation results. Parent node: Groups

Vector retrieval

Name	Type	Example	Description
MetaQuery	Container	N/A	The container for query results. Child node: Files
Files	Container	N/A	The list of object information. Child node: File Parent node: MetaQuery
File	Container	N/A	The information about a single object. Parent node: Files
URI	String	oss://examplebucket/test-object.jpg	The full path of the object. Parent node: File
Filename	String	exampleobject.txt	The name of the object. Parent node: File
Size	Integer	120	The size of the object in bytes. Parent node: File
ObjectACL	String	default	The ACL of the object. Valid values: default: Inherits the bucket ACL. private: Only the object owner and authorized users can read and write. Other users cannot access the object. public-read: The owner and authorized users can read and write. Other users can only read. Use with caution. public-read-write: All users can read and write. Use with caution. Parent node: File
FileModifiedTime	String	2025-05-19T16:15:33+08:00	The last modified time of the object. The format is RFC3339Nano. Parent node: File
ETag	String	"fba9dede5f27731c9771645a3986****"	An ETag is generated when an object is created. It identifies the content of the object. For an object created by a PutObject request, the ETag value is the MD5 hash of its content. For objects created by other methods, the ETag is a unique value but not the MD5 hash of the content. Note You can use the ETag to check whether object content has changed, but do not use it as the MD5 hash for data integrity verification. Parent node: File
OSSCRC64	String	4858A48BD1466884	The 64-bit CRC value of the object. The 64-bit CRC value is calculated based on the CRC-64/XZ standard. Parent node: File
ProduceTime	String	2021-06-29T14:50:13.011643661+08:00	The time when the photo or video was captured by the device. Parent node: File
ContentType	String	image/jpeg	The Multipurpose Internet Mail Extensions (MIME) type. Parent node: File
MediaType	String	image	The media type. Parent node: File
LatLong	String	30.134390,120.074997	The latitude and longitude information. Parent node: File
Title	String	test	The title of the file. Parent node: File
OSSExpiration	String	2124-12-01T12:00:00.000Z	The expiration time of the file. Parent node: File
AccessControlAllowOrigin	String	https://aliyundoc.com	The origin that is allowed to send cross-origin requests. Parent node: File
AccessControlRequestMethod	String	PUT	The method used in the cross-origin request. Parent node: File
CacheControl	String	no-cache	The web page caching behavior when the object is downloaded. Parent node: File
ContentDisposition	String	attachment; filename =test.jpg	The name of the object when it is downloaded. Parent node: File
ContentEncoding	String	UTF-8	The content encoding format when the object is downloaded. Parent node: File
ContentLanguage	String	zh-CN	The language used in the object content. Parent node: File
ImageHeight	Integer	500	The height of the image in pixels (px). Parent node: File
ImageWidth	Integer	270	The width of the image in pixels (px). Parent node: File
VideoWidth	Integer	1080	The width of the video frame in pixels (px). Parent node: File
VideoHeight	Integer	1920	The height of the video frame in pixels (px). Parent node: File
VideoStreams	Container	N/A	The list of video streams. Parent node: File
VideoStream	Container	N/A	The video stream. Parent node: VideoStreams
CodecName	String	h264	The name of the encoder. Parent node: VideoStream
Language	String	en	The language used in the video stream. The format is BCP 47. Parent node: VideoStream
Bitrate	Integer	5407765	The bitrate in bit/s. Parent node: VideoStream
FrameRate	String	25/1	The frame rate of the video stream. Parent node: VideoStream
StartTime	Double-precision floating-point number	0.000000	The start time of the video stream in seconds (s). Parent node: VideoStream
Duration	Double-precision floating-point number	22.88	The duration of the video stream in seconds (s). Parent node: VideoStream
FrameCount	Integer	572	The number of video frames. Parent node: VideoStream
BitDepth	Integer	8	The pixel bit depth. Parent node: VideoStream
PixelFormat	String	yuv420p	The pixel format of the video stream. Parent node: VideoStream
ColorSpace	String	bt709	The color space. Parent node: VideoStream
Height	Integer	720	The height of the video stream frame in pixels (px). Parent node: VideoStream
Width	Integer	1280	The width of the video stream frame in pixels (px). Parent node: VideoStream
AudioStreams	Container	N/A	The list of audio streams. Parent node: File
AudioStream	Container	N/A	The audio stream. Parent node: AudioStreams
CodecName	String	aac	The name of the encoder. Parent node: AudioStream
Bitrate	Integer	320087	The bitrate in bit/s. Parent node: AudioStream
SampleRate	Integer	48000	The sample rate in hertz (Hz). Parent node: AudioStream
StartTime	Double-precision floating-point number	0.0235	The start time of the audio stream in seconds (s). Parent node: AudioStream
Duration	Double-precision floating-point number	3.690667	The duration of the audio stream in seconds (s). Parent node: AudioStream
Channels	Integer	2	The number of sound channels. Parent node: AudioStream
Language	String	en	The language used in the audio stream. The format is BCP 47. Parent node: AudioStream
Subtitles	Container	N/A	The list of caption streams. Parent node: File
Subtitle	Container	N/A	The caption stream. Parent node: Subtitles
CodecName	String	mov_text	The name of the encoder. Parent node: Subtitle
Language	String	en	The language of the caption. The format is BCP 47. Parent node: Subtitle
StartTime	Double-precision floating-point number	0.000000	The start time of the caption stream in seconds (s). Parent node: Subtitle
Duration	Double-precision floating-point number	71.378	The duration of the caption stream in seconds (s). Parent node: Subtitle
Bitrate	Integer	13091201	The bitrate in bit/s. Parent node: File
Artist	String	Jane	The artist. Parent node: File
AlbumArtist	String	Jenny	Artist. Parent node: File
Composer	String	Jane	The composer. Parent node: File
Performer	String	Jane	The performer. Parent node: File
Album	String	FirstAlbum	The album. Parent node: File
Duration	Double-precision floating-point number	15.263000	The total duration of the video in seconds. Parent node: File
Addresses	Container	N/A	The address information. Parent node: File
Address	Container	N/A	The address information. Parent node: Addresses
AddressLine	String	No. 969, Wenyi West Road, Yuhang District, Hangzhou, Zhejiang, China	The full address. Parent node: Address
City	String	Hangzhou	The city. Parent node: Address
District	String	Yuhang District	The district. Parent node: Address
Language	String	zh-Hans	The language. The format is BCP 47. Parent node: Address
Province	String	Zhejiang	The province. Parent node: Address
Township	String	Wenyi West Road	The street. Parent node: Address
OSSObjectType	String	Normal	The type of the object. Parent node: File
OSSStorageClass	String	Standard	The storage class of the object. Parent node: File
OSSTaggingCount	Integer	2	The number of tags of the object. Parent node: File
OSSTagging	Container	N/A	The list of tag information. Child node: Tagging Parent node: File
Tagging	Container	N/A	The container for a single tag. Child nodes: Key and Value Parent node: OSSTagging
Key	String	owner	The key of the tag. Parent node: Tagging
Value	String	John	The value of the tag. Parent node: Tagging
Key	String	owner	The key of the user-defined metadata. Parent node: Tagging
Value	String	John	The value of the user-defined metadata. Parent node: Tagging
Insights	Container	N/A	The description of the file. Child nodes: Video and Image
Video	Container	N/A	The description of the video file. Parent node: Insights Child nodes: Caption and Description
Caption	String	N/A	A brief description. Parent node: Video
Image	Container	N/A	The description of the image file. Parent node: Insights Child nodes: Caption and Description
Caption	String	N/A	A brief description. Parent node: Image
Description	String	N/A	A detailed description. Parent node: Image

Examples

Request examples

Scalar retrieval

POST /?metaQuery&comp=query&mode=basic HTTP/1.1
Host: BucketName.oss-cn-hangzhou.aliyuncs.com
Date: GMT Date
Authorization: SignatureValue 
<?xml version="1.0" encoding="UTF-8"?>
<MetaQuery>
  <NextToken></NextToken>
  <MaxResults>5</MaxResults>
  <Query>{"Field": "Size","Value": "1048576","Operation": "gt"}</Query>
  <Sort>Size</Sort>
  <Order>asc</Order>
  <Aggregations>
    <Aggregation>
      <Field>Size</Field>
      <Operation>sum</Operation>
    </Aggregation>
    <Aggregation>
      <Field>Size</Field>
      <Operation>max</Operation>
    </Aggregation>
  </Aggregations>
</MetaQuery>

Vector retrieval

POST /?metaQuery&comp=query&mode=semantic HTTP/1.1
Host: BucketName.oss-cn-hangzhou.aliyuncs.com
Date: Thu, 12 Sep 2024 13:08:38 GMT
Authorization: SignatureValue 
<?xml version="1.0" encoding="UTF-8"?>
<MetaQuery>
  <MaxResults>99</MaxResults>
  <Query>An aerial view of a snow-covered forest</Query> // Required
  <MediaTypes>
    <MediaType>image</MediaType>
  </MediaTypes>
  // SimpleQuery is equivalent to the Query field in simple mode.
  <SimpleQuery>{"Operation":"gt", "Field": "Size", "Value": "30"}</SimpleQuery>
</MetaQuery>

Response examples

Scalar retrieval

HTTP/1.1 200 OK
x-oss-request-id: 5C1B138A109F4E405B2D****
Date: Mon, 26 Jul 2021 13:08:38 GMT
Content-Length: 118
Content-Type: application/xml
Connection: keep-alive
Server: AliyunOSS
<?xml version="1.0" encoding="UTF-8"?>
<MetaQuery>
  <NextToken>MTIzNDU2Nzg6aW1tdGVzdDpleGFtcGxlYnVja2V0OmRhdGFzZXQwMDE6b3NzOi8vZXhhbXBsZWJ1Y2tldC9zYW1wbGVvYmplY3QxLmpw****</NextToken>
  <Files>
    <File>
      <Filename>exampleobject.txt</Filename>
      <Size>120</Size>
      <FileModifiedTime>2025-05-19T16:14:38+08:00</FileModifiedTime>
      <OSSObjectType>Normal</OSSObjectType>
      <OSSStorageClass>Standard</OSSStorageClass>
      <ObjectACL>default</ObjectACL>
      <ETag>"fba9dede5f27731c9771645a3986****"</ETag>
      <OSSCRC64>4858A48BD1466884</OSSCRC64>
      <OSSTaggingCount>2</OSSTaggingCount>
      <OSSTagging>
        <Tagging>
          <Key>owner</Key>
          <Value>John</Value>
        </Tagging>
        <Tagging>
          <Key>type</Key>
          <Value>document</Value>
        </Tagging>
      </OSSTagging>
    </File>
  </Files>
</MetaQuery>

Vector retrieval

Example of a response for an image retrieval request with insights

HTTP/1.1 200 OK
x-oss-request-id: 5C1B138A109F4E405B2D****
Date: Thu, 12 Sep 2024 13:08:38 GMT
Content-Length: 118
Content-Type: application/xml
Connection: keep-alive
Server: AliyunOSS
<?xml version=\"1.0\" encoding=\"UTF-8\"?>
<MetaQuery>
  <Files>
    <File>
      <URI>oss://examplebucket/test-object.jpg</URI>
      <Filename>sampleobject.jpg</Filename>
      <Size>1000</Size>
      <ObjectACL>default</ObjectACL>
      <FileModifiedTime>2025-05-19T16:14:38+08:00</FileModifiedTime>
      <ETag>\"1D9C280A7C4F67F7EF873E28449****\"</ETag>
      <OSSCRC64>559890638950338001</OSSCRC64>
      <ProduceTime>2021-06-29T14:50:15.011643661+08:00</ProduceTime>
      <ContentType>image/jpeg</ContentType>
      <MediaType>image</MediaType>
      <LatLong>30.134390,120.074997</LatLong>
      <Title>test</Title>
      <OSSExpiration>2024-12-01T12:00:00.000Z</OSSExpiration>
      <AccessControlAllowOrigin>https://aliyundoc.com</AccessControlAllowOrigin>
      <AccessControlRequestMethod>PUT</AccessControlRequestMethod>
      <CacheControl>no-cache</CacheControl>
      <ContentDisposition>attachment; filename =test.jpg</ContentDisposition>
      <ContentEncoding>UTF-8</ContentEncoding>
      <ContentLanguage>zh-CN</ContentLanguage>
      <ImageHeight>500</ImageHeight>
      <ImageWidth>270</ImageWidth>
      <Addresses>
        <Address>
          <AddressLine>No. 969, Wenyi West Road, Yuhang District, Hangzhou, Zhejiang, China</AddressLine>
          <City>Hangzhou</City>
          <Country>China</Country>
          <District>Yuhang District</District>
          <Language>zh-Hans</Language>
          <Province>Zhejiang</Province>
          <Township>Wenyi West Road</Township>
        </Address>
        <Address>
          <AddressLine>No. 970, Wenyi West Road, Yuhang District, Hangzhou, Zhejiang, China</AddressLine>
          <City>Hangzhou</City>
          <Country>China</Country>
          <District>Yuhang District</District>
          <Language>zh-Hans</Language>
          <Province>Zhejiang</Province>
          <Township>Wenyi West Road</Township>
        </Address>
      </Addresses>
      <OSSObjectType>Normal</OSSObjectType>
      <OSSStorageClass>Standard</OSSStorageClass>
      <OSSTaggingCount>2</OSSTaggingCount>
      <OSSTagging>
        <Tagging>
          <Key>key</Key>
          <Value>val</Value>
        </Tagging>
        <Tagging>
          <Key>key</Key>
          <Value>val</Value>
        </Tagging>
      </OSSTagging>
      <Insights>
        <Image>
          <Caption>A person is standing.</Caption>
          <Description>The image shows a person who wears a dark suit jacket over a white shirt. The background is a gradient from light blue to gray.</Description>
        </Image>
      </Insights>
    </File>
  </Files>
</MetaQuery>

Example of a response for an audio or video retrieval request with insights

HTTP/1.1 200 OK
x-oss-request-id: 5C1B138A109F4E405B2D****
Date: Thu, 12 Sep 2024 13:08:38 GMT
Content-Length: 118
Content-Type: application/xml
Connection: keep-alive
Server: AliyunOSS
<?xml version=\"1.0\" encoding=\"UTF-8\"?>
<MetaQuery>
  <Files>
    <File>
      <URI>oss://examplebucket/test-object.jpg</URI>
      <Filename>sampleobject.jpg</Filename>
      <Size>1000</Size>
      <ObjectACL>default</ObjectACL>
      <FileModifiedTime>2021-06-29T14:50:14.011643661+08:00</FileModifiedTime>
      <ETag>\"1D9C280A7C4F67F7EF873E28449****\"</ETag>
      <OSSCRC64>559890638950338001</OSSCRC64>
      <ProduceTime>2021-06-29T14:50:15.011643661+08:00</ProduceTime>
      <ContentType>image/jpeg</ContentType>
      <MediaType>image</MediaType>
      <LatLong>30.134390,120.074997</LatLong>
      <Title>test</Title>
      <OSSExpiration>2024-12-01T12:00:00.000Z</OSSExpiration>
      <AccessControlAllowOrigin>https://aliyundoc.com</AccessControlAllowOrigin>
      <AccessControlRequestMethod>PUT</AccessControlRequestMethod>
      <CacheControl>no-cache</CacheControl>
      <ContentDisposition>attachment; filename =test.jpg</ContentDisposition>
      <ContentEncoding>UTF-8</ContentEncoding>
      <ContentLanguage>zh-CN</ContentLanguage>
      <VideoWidth>1080</VideoWidth>
      <VideoHeight>1920</VideoHeight>
      <VideoStreams>
        <VideoStream>
          <CodecName>h264</CodecName>
          <Language>en</Language>
          <Bitrate>5407765</Bitrate>
          <FrameRate>25/1</FrameRate>
          <StartTime>0</StartTime>
          <Duration>22.88</Duration>
          <FrameCount>572</FrameCount>
          <BitDepth>8</BitDepth>
          <PixelFormat>yuv420p</PixelFormat>
          <ColorSpace>bt709</ColorSpace>
          <Height>720</Height>
          <Width>1280</Width>
        </VideoStream>
        <VideoStream>
          <CodecName>h264</CodecName>
          <Language>en</Language>
          <Bitrate>5407765</Bitrate>
          <FrameRate>25/1</FrameRate>
          <StartTime>0</StartTime>
          <Duration>22.88</Duration>
          <FrameCount>572</FrameCount>
          <BitDepth>8</BitDepth>
          <PixelFormat>yuv420p</PixelFormat>
          <ColorSpace>bt709</ColorSpace>
          <Height>720</Height>
          <Width>1280</Width>
        </VideoStream>
      </VideoStreams>
      <AudioStreams>
        <AudioStream>
          <CodecName>aac</CodecName>
          <Bitrate>1048576</Bitrate>
          <SampleRate>48000</SampleRate>
          <StartTime>0.0235</StartTime>
          <Duration>3.690667</Duration>
          <Channels>2</Channels>
          <Language>en</Language>
        </AudioStream>
      </AudioStreams>
      <Subtitles>
        <Subtitle>
          <CodecName>mov_text</CodecName>
          <Language>en</Language>
          <StartTime>0</StartTime>
          <Duration>71.378</Duration>
        </Subtitle>
        <Subtitle>
          <CodecName>mov_text</CodecName>
          <Language>en</Language>
          <StartTime>72</StartTime>
          <Duration>71.378</Duration>
        </Subtitle>
      </Subtitles>
      <Bitrate>5407765</Bitrate>
      <Artist>Jane</Artist>
      <AlbumArtist>Jenny</AlbumArtist>
      <Composer>Jane</Composer>
      <Performer>Jane</Performer>
      <Album>FirstAlbum</Album>
      <Duration>71.378</Duration>
      <Addresses>
        <Address>
          <AddressLine>No. 969, Wenyi West Road, Yuhang District, Hangzhou, Zhejiang, China</AddressLine>
          <City>Hangzhou</City>
          <Country>China</Country>
          <District>Yuhang District</District>
          <Language>zh-Hans</Language>
          <Province>Zhejiang</Province>
          <Township>Wenyi West Road</Township>
        </Address>
        <Address>
          <AddressLine>No. 970, Wenyi West Road, Yuhang District, Hangzhou, Zhejiang, China</AddressLine>
          <City>Hangzhou</City>
          <Country>China</Country>
          <District>Yuhang District</District>
          <Language>zh-Hans</Language>
          <Province>Zhejiang</Province>
          <Township>Wenyi West Road</Township>
        </Address>
      </Addresses>
      <OSSObjectType>Normal</OSSObjectType>
      <OSSStorageClass>Standard</OSSStorageClass>
      <OSSTaggingCount>2</OSSTaggingCount>
      <OSSTagging>
        <Tagging>
          <Key>key</Key>
          <Value>val</Value>
        </Tagging>
        <Tagging>
          <Key>key</Key>
          <Value>val</Value>
        </Tagging>
      </OSSTagging>
      <Insights>
        <Video>
          <Caption>The video shows two scenes: a still life with a white plate, a black bottle, and a transparent glass, and a hand holding a shampoo bottle labeled "YEZOLU" and moving it slowly upwards in a bathroom.</Caption>
        </Video>
      </Insights>
    </File>
  </Files>
</MetaQuery>

Query examples

Nest Query elements to build complex query conditions and precisely retrieve the content you need.

To search for an object named exampleobject.txt that is smaller than 1000 bytes, configure the Query element as follows:


{
  "SubQueries":[
    {
      "Field":"Filename",
      "Value": "exampleobject.txt",
      "Operation":"eq"
    },         
    {
      "Field":"Size",
      "Value":"1000",
      "Operation":"lt"
    }
  ],
  "Operation":"and"
}

To search for objects that have the exampledir/ prefix, contain the type=document or owner=John tag, and are larger than 10 MB, configure the Query element as follows:


{
  "SubQueries": [
    {
      "Field": "Filename",
      "Value": "exampledir/",
      "Operation": "prefix"
    },
    {
      "Field": "Size",
      "Value": "1048576",
      "Operation": "gt"
    },
    {
      "SubQueries": [
        {
          "Field": "OSSTagging.type",
          "Value": "document",
          "Operation": "eq"
        },
        {
          "Field": "OSSTagging.owner",
          "Value": "John",
          "Operation": "eq"
        }
      ],
      "Operation": "or"
    }
  ],
  "Operation": "and"
}

Beyond search conditions, you can use aggregate operations to perform statistical analysis — such as total size, count, average, max, or min — on objects that match the criteria, or analyze size distribution of matching images.

SDK

SDKs available for this operation:

ossutil command-line tool

The DoMetaQuery operation corresponds to the do-meta-query command in ossutil.