建表
create table <table_name>(
column_name1 column_type [not null] [check (expression)]
[default value] [primary key][references <table_name>(column_name)],
column_name2 column_type [not null] [check (expression)]
[default value] [primary key][references <table_name>(column_name)]
....
[constraint primary_name
primary key(column_name1,column_name2...)
]
[unique(<column_name1,column_name2...>)]
);
create table <table_name>
as
select * from <other_table_name> where <condition>
---------------------------------------------------------------------------------------
改表结构
1 alter table <table_name> add(column_name column_type);
2 alter table <table_name> modify(column_naem column_type);
----------------------------------------- ......
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