into outfile/load data infile

mysql的into outfile/load data infile可以用于数据的导入导出。

跟mysqldump不同的是，into outfile直接将数据输出到问题，数据本身是没有加密的，文件本身没有ddl建表语句，也没有insert语句。相当于将表数据导成csv表格文件

 

select .. into outfile语法：

SELECT
...

into_option: {
    INTO OUTFILE 'file_name'
        [CHARACTER SET charset_name]
        export_options
  | INTO DUMPFILE 'file_name'
  | INTO var_name [, var_name] ...
}

load data infile ..into table语法

LOAD DATA
    [LOW_PRIORITY | CONCURRENT] [LOCAL]
    INFILE 'file_name'
    [REPLACE | IGNORE]
    INTO TABLE tbl_name
    [PARTITION (partition_name [, partition_name] ...)]
    [CHARACTER SET charset_name]
    [{FIELDS | COLUMNS}
        [TERMINATED BY 'string']
        [[OPTIONALLY] ENCLOSED BY 'char']
        [ESCAPED BY 'char']
    ]
    [LINES
        [STARTING BY 'string']
        [TERMINATED BY 'string']
    ]
    [IGNORE number {LINES | ROWS}]
    [(col_name_or_user_var
        [, col_name_or_user_var] ...)]
    [SET col_name={expr | DEFAULT}
        [, col_name={expr | DEFAULT}] ...]

 

虽然语法选项很多，其中fields terminated by ',' enclosed by '`' lines terminated by '\r\n'是比较关键的

fields terminated by ','    以  , 分割字段

enclosed by '`'  以 ` 围起字段，如果没有enclose可能导入时会遇到识别字段的问题，比如数据本身有,号，识别就错位了

lines terminated by '\r\n'   \r\n为换行符， \r\n是linux的换行符，如果没有换行符导入数据可能只有1行

当然符号是自定义的，尽量使用数据中不太可能出现的字符

 

导出测试：

mysql> select * from lzldb.test1 into outfile '/tmp/lzldb_test1.txt' fields terminated by ','  enclosed by '`' lines terminated by '\r\n' ;
Query OK, 7 rows affected (0.01 sec)

mysql> create table lzldb.test2 like lzldb.test1;
Query OK, 0 rows affected (0.02 sec)
mysql> load data infile '/tmp/lzldb_test1.txt' into table lzldb.test2 fields  terminated by ','  enclosed by '`' lines terminated by '\r\n'   ;
Query OK, 7 rows affected (0.00 sec)
Records: 7  Deleted: 0  Skipped: 0  Warnings: 0