- You can use ">>" to export the query results to a file, the syntax is like `select * from table >> file`. If there is only file name without path, the file will be generated under the current working directory of TDegnine CLI.
## Import data from CSV file
- You can use `insert into table_name file 'fileName'` to import the data from the specified file into the specified table. For example, `insert into d0 file '/root/d0.csv';` means importing the data in file "/root/d0.csv" into table "d0". If there is only file name without path, that means the file is located under current working directory of TDengine CLI.
## TDengine CLI tips
- You can use the up and down keys to iterate the history of commands entered
- Execute `RESET QUERY CACHE` to clear the local cache of the table schema
- Execute SQL statements in batches. You can store a series of shell commands (ending with ;, one line for each SQL command) in a script file and execute the command `source <file-name>` in the TDengine CLI to execute all SQL commands in that file automatically
os.system("LD_LIBRARY_PATH=/usr/lib taos -s 'flush database test '")
# os.system(f"LD_LIBRARY_PATH=/usr/lib taos -s 'use test;create stream current_stream into current_stream_output_stb as select _wstart as `start`, _wend as wend, max(current) as max_current from meters where voltage <= 220 interval (5s);' ")
# os.system('LD_LIBRARY_PATH=/usr/lib taos -s "use test;create stream power_stream into power_stream_output_stb as select ts, concat_ws(\\".\\", location, tbname) as meter_location, current*voltage*cos(phase) as active_power, current*voltage*sin(phase) as reactive_power from meters partition by tbname;" ')
