mysql base operations

1. The construction of the table

create table table name (data type of a field [Column Properties], the second data type field [Column Properties], .........) [Table Type] [Table Character Set] [Note];

Note: MySQL command terminator is the semicolon . 

1) Table name:

       Table names can be specified in order to create a table called in a particular database db_name as db_name.tb_name,, if it is in the current database, db_name can be omitted, but with tb_name.

       If you use the escape character in `mysql table and to avoid  keyword conflicts mysql itself, it should have the database and table names are added`.

       For example, `mydb`.`mytbl` is legal, but` mydb.mytbl` illegal.

                Is `  MySQL's escape character , used to avoid column and table names and  keyword conflicts mysql itself.

                  Some databases have a similar setup, but mysql using a `only. Which is usually used to describe the contents of the database names, table names, field names, not keywords.

     For example, the SELECT * from `key` the WHERE table_name = 'key_name' ; which, mysql keyword is the key, if the column name is the key, then you need to escape it with` `.

       Extended: strings need to use \ to escape the `, otherwise it will error prompt syntax error.

        mysql -uUser -pPasswd -e "select * from table_name where \`key\` = 'name';"

2) common data types

       MySQL Data Types

      https://www.cnblogs.com/-xlp/p/8617760.html

3) The column properties

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

       mysql 6 columns attributes: null, not null, default, comment, primary key, unique key, auto_increment

       https://blog.csdn.net/csxiaoyaojianxian/article/details/80793561

                  Some databases have a similar setup, but mysql using a `only. Which is usually used to describe the contents of the database names, table names, field names, not keywords.

     For example, the SELECT * from `key` the WHERE table_name = 'key_name' ; which, mysql keyword is the key, if the column name is the key, then you need to escape it with` `.

       Extended: strings need to use \ to escape the `, otherwise it will error prompt syntax error.

        mysql -uUser -pPasswd -e "select * from table_name where \`key\` = 'name';"

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Origin www.cnblogs.com/ting152/p/12448103.html