TDengine/docs/examples/python/reference_connection.py

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from dotenv import load_dotenv
# read .env file from current working directory
load_dotenv()
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# ANCHOR: example
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import taosrest
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# ANCHOR: connect
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import os
url = os.environ["TDENGINE_CLOUD_URL"]
token = os.environ["TDENGINE_CLOUD_TOKEN"]
conn = taosrest.connect(url=url, token=token)
# test the connection by getting version info
print("server version:", conn.server_info)
# ANCHOR_END: connect
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affected_row = conn.execute("CREATE STABLE IF NOT EXISTS power.meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)")
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print("affected_row", affected_row) # 0
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affected_row = conn.execute("""INSERT INTO
power.d1001 USING power.meters TAGS('California.SanFrancisco', 2) VALUES ('2018-10-03 14:38:05.000', 10.30000, 219, 0.31000) ('2018-10-03 14:38:15.000', 12.60000, 218, 0.33000) ('2018-10-03 14:38:20.800', 12.30000, 221, 0.31000)
power.d1002 USING power.meters TAGS('California.SanFrancisco', 3) VALUES ('2018-10-03 14:39:19.650', 10.30000, 218, 0.25000)
power.d1003 USING power.meters TAGS('California.LosAngeles', 2) VALUES ('2018-10-03 14:41:05.500', 11.80000, 221, 0.28000) ('2018-10-03 14:42:16.600', 13.40000, 223, 0.29000)
power.d1004 USING power.meters TAGS('California.LosAngeles', 3) VALUES ('2018-10-03 14:48:05.000', 10.80000, 223, 0.29000) ('2018-10-03 14:55:06.500', 11.50000, 221, 0.35000)
""")
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print("affected_row", affected_row) # 8
result = conn.query("SELECT ts, current FROM power.meters LIMIT 2")
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print("metadata of each column:\n", result.fields)
# [{'name': 'ts', 'type': 'TIMESTAMP', 'bytes': 8}, {'name': 'current', 'type': 'FLOAT', 'bytes': 4}]
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print("total rows:", result.rows) # 2
# Iterate over result.
for row in result:
print(row)
# output:
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# [datetime.datetime(2018, 10, 3, 14, 38, 5), 10.3]
# [datetime.datetime(2018, 10, 3, 14, 38, 15), 12.6]
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# Or get all rows as a list
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print(result.data)
# [[datetime.datetime(2018, 10, 3, 14, 38, 5), 10.3], [datetime.datetime(2018, 10, 3, 14, 38, 15), 12.6]]
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# ANCHOR_END: example
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