显示数据库：show databases；
创建数据库：CREATE DATABASE IF NOT EXISTS <db_name>
显示数据库中有哪些超级表：show stables;
创建超级表：CREATE STABLE <stable_name>(ts timestamp, longitude double, latitude double, tgtheight float, course float, speed float, fusiontype int, fusionsrccnt tinyint, fusionsrcs nchar(200)) TAGS (starttime timestamp);
删除超级表：DROP STABLE IF EXISTS <stable_name>;
查看表结构：describe <table_name>；
查看表中数据：SELECT * FROM <table_name>;
查询是否存在某张表：select count(*) from information_schema.ins_tables where db_name='<db_name>' and table_name='<table_name>';
查询某个超级表下所有子表表名：select table_name from information_schema.ins_tables where db_name='<db_name>' and stable_name='<stable_name>';
查询数据库中有哪些超表：select stable_name from information_schema.ins_stables where db_name='<db_name>';
超级表新增Tag：ALTER TABLE <stable_name> add tag <tag_name> <tag_data_type>;
删除超级表Tag：ALTER TABLE <stable_name> DROP TAG <tag_name>;
标签值Tag与count(*)一起查询：select <tag_name>,count(*) from <table_name> group by <tag_name>;
查询表最后一条数据：select * from <table_name> order by ts desc limit 1;
查看数据库有几个表（不含超表）：select count(*) from information_schema.ins_tables where db_name='<db_name>';
查看超级表下有几个子表：select count(*) from information_schema.ins_tables where db_name='<db_name>' and stable_name='<stable_name>';
查看超级表下有几个子表（2）：select count(<tag_name>) from (select <tag_name> from <stable_name> group by <tag_name>);
order by 、group by 与 limit 一起使用时：select * from (select * from <stable_name> where <tag_name> > 220822999000804 group by <tag_name>) order by <tag_name> limit 10;
[量化投资-学习笔记001]Python+TDengine从零开始搭建量化分析平台-数据存储_DBA大董的技术博客_51CTO博客
