Query Operation

Last Updated：2020-07-20

Get the Metric

The following code can get the metric list:

# get metric lists
result = tsdb_client.get_metrics()
print result.metrics

Return result:

[u'wind']

Get the Field

The following code can get the Field objects:

metric = 'wind' # metric that the field to get belongs to
result = tsdb_client.get_fields(metric) # get all the fields under the appointed metric
print result.fields

Return result:

{direction:{type:u'Number'},speed:{type:u'Number'}}

Get the Tag

The following code can get the Tag objects:

metric = 'wind' # metric that the tag to get belongs to
result = tsdb_client.get_tags(metric)
print result.tags

Return result:

{city:[u'ShangHai']}

Query Data Points

Query Single-Field Data Points

The following code can query single-field data points:

# build query objects
query_list = [{
    "metric": "wind",
    "field": "direction",
    "filters": {
        "start": 1531985370000,
        "end": 1531985400000,
        "tags": {
            "city": ["ShangHai"]
        },
        "value": ">= 0"
    },
    "groupBy": [{
        "name": "Tag",
        "tags": ["city"]
    }],
    "limit": 1000,
    "aggregators": [{
        "name": "Sum",
        "sampling": "10 minutes"
    }]
}]
result = tsdb_client.get_datapoints(query_list)
print result.results

Return result:

[{field:u'direction',metric:u'wind',groups:[{group_infos:[{name:u'Tag',tags:{city:u'ShangHai'}}],values:[[1531985379000, 2]]}],rawcount:2}]

Query Multiple-Field Data Points

The following code can query multiple-field data points:

# build query objects
query_list = [{
    "metric": "wind",
    "fields": ["direction", "speed"],   # query multiple fields
    "filters": {
        "start": 1531985370000,
        "end": 1531985400000,
        "tags": {
            "city": ["ShangHai"]
        },
        "value": ">= 0"
    },
    "groupBy": [{
        "name": "Tag",
        "tags": ["city"]
    }],
    "limit": 1000,
    "aggregators": [{
        "name": "Sum",
        "sampling": "10 minutes"
    }]
}]
result = tsdb_client.get_datapoints(query_list)
print result.results

Return result:

[{fields:[u'direction', u'speed'],metric:u'wind',groups:[{group_infos:[{name:u'Tag',tags:{city:u'ShangHai'}}],values:[[1531985380000, 1, 4.5]]}],rawcount:1}]

Query Data Points Using Interpolation

Use following code for interpolation query:

# build query objects
query_list = [{
    "metric": "wind",
    "fields": ["direction", "speed"],
    "filters": {
        "start": 1531985370000,
        "end": 1532985370000,
        "tags": {
            "city": ["ShangHai"]
        },
        "value": ">= 0"
    },
    "fill": {                             # configure interpolation parameters
        "type": "Linear",                 # interpolation type
        "interval": "1 day",              # interpolation interval
        "maxWriteInterval": "30 minutes"  # max write interval
    },
    "groupBy": [{
        "name": "Tag",
        "tags": ["city"]
    }],
    "limit": 1000,
    "aggregators": [{
        "name": "Sum",
        "sampling": "10 minutes"
    }]
}]
 
result = tsdb_client.get_datapoints(query_list)
print result.results

Return result:

[{fields:[u'direction', u'speed'],metric:u'wind',groups:[{group_infos:[{name:u'Tag',tags:{city:u'ShangHai'}}],values:[[1531985380000, 1, 4.5], [1532071780000, 1, 4.5], [1532158180000, 1, 4.5], [1532244580000, 1, 4.5], [1532330980000, 1, 4.5], [1532417380000, 1, 4.5], [1532503780000, 1, 4.5], [1532590180000, 1, 4.5], [1532676580000, 1, 4.5], [1532762980000, 1, 4.5], [1532849380000, 1, 4.5], [1532935780000, 1, 4.5]]}],rawcount:12}]

Paging Query Data Points

If the original data point queried is too large, it will be returned several times and the marker parameter will be used for paging query.

# query data multiple times through loop
 
query_list = [{
    "metric": "wind",
    "field": "direction",
    "filters": {
        "start": 1531985300000,
        "end": 1531985400000,
        "tags": {
            "city": ["ShangHai"]
        }
    },
    "limit": 1
}]
count = 0
while True:
    count += 1
    if len(query_list) >0:
        result = tsdb_client.get_datapoints(query_list)
        print count, result.results
    else:
        print 'end query'
        break
    next_query = []
    for i in range(len(query_list)):
        if result.results[i].truncated:
            query_list[i]['marker'] = result.results[i].next_marker
            next_query.append(query_list[i])
    query_list = next_query

Return result:

1 [{field:u'direction',next_marker:u'AAABZLFxwqBjaXR5PVNoYW5nSGFp',groups:[{group_infos:[],values:[[1531985379000, 1]]}],truncated:True,metric:u'wind',rawcount:1}]
2 [{field:u'direction',metric:u'wind',groups:[{group_infos:[],values:[[1531985380000, 1]]}],rawcount:1}]
end query

Query Data Points Using SQL

TSDB supports data queries using SQL. The example code is as follows:

sql = "select * from wind"
result = tsdb_client.get_rows_with_sql(sql)
print result

Return result:

{rows:[[1531985379000, 1.0, None, u'ShangHai'], [1531985380000, 1.0, 4.5, u'ShangHai']],columns:[{name:u'timestamp'}, {name:u'direction'}, {name:u'speed'}, {name:u'city'}],metadata:{content_length:'168',content_type:'application/json; charset=UTF-8',keep_alive:'timeout=10',server:'BWS',connection:'keep-alive',pragma:'no-cache',date:'Thu, 02 Aug 2018 00:35:28 GMT',bce_request_id:'46f5d19e-58de-4654-bc35-91bb67b58e76',cache_control:'no-cache'}}

Write Operation

Generate the Pre-Signed URL of Querying Data Points

百度智能云

Time-Spatial Database

Query Operation

Get the Metric

Get the Field

Get the Tag

Query Data Points

Query Single-Field Data Points

Query Multiple-Field Data Points

Query Data Points Using Interpolation

Paging Query Data Points

Query Data Points Using SQL