[TIL] SQL/Table

💻 실습

table 문법

table 생성

create table tablename (
	columnname datatype,
    columnname datatype,
    ...
);

table 목록확인

show tables;

table 정보확인

desc tablename;

table name 변경

alter table tablename
rename new_tablename;

table column 추가

alter table tablename
add column columnname datatype;

table column 변경

alter table tablename
modify column columnname datatype; //datatype

alter table tablename
change column old_columnname new_columnname new_datatype; //name

table column 삭제

alter table tablename
drop column columnname;

table 삭제

drop table tablename;

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🧸 review

example table

create table example
(
   id int,
   name varchar(16)
);

• age(int) column 추가

alter table example
add column age int;

• old(int) column 추가

alter table example
add column old int;

• age(int) column 삭제

alter table example
drop column age;

• old(int) → sex(char) column 변경

alter table example
change column old sex char;

• animal table 삭제

drop table animal;

🚫 table 생성 전에 데이터베이스 설정하기

실습확인

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