数据操作语句（Data Manipulation Language）
Delete
单表语法：
DELETE [LOW_PRIORITY] [QUICK] [IGNORE] FROM tbl_name
[WHERE where_definition]
[ORDER BY ...]
[LIMIT row_count]多表语法：
DELETE [LOW_PRIORITY] [QUICK] [IGNORE]
tbl_name[.*] [, tbl_name[.*] ...]
FROM table_references
[WHERE where_definition]或：
DELETE [LOW_PRIORITY] [QUICK] [IGNORE]
FROM tbl_name[.*] [, tbl_name[.*] ...]
USING table_references
[WHERE where_definition]tbl_name中有些行满足where_definition给定的条件。Delete用于删除这些行，并且返回被删除记录的数目。
Insert
insert into tbl_name [(field1,field2,field3…fieldN)]
values
(value1,value2,value3…valueN)Insert用于向一个已有的表插入新行。
insert into tbl_name [(field1,field2,field3…fieldN)]
select …
例如，
INSERT INTO tbl_temp2 (fld_id)
SELECT tbl_temp1.fld_order_id
FROM tbl_temp1 WHERE tbl_temp1.fld_order_id > 100;
Select
select column_name
[from table_reference]
[where where_definition]
[group by {column_name}]
[asc| desc ]
[having where_definition]
[oder by {column_name}]
[limit n]
[offset n]Select语句用于从一个或多个表中选择行，并可以加入union和子查询。
其中 group by 和having 常常连在一起用。limit限制查询结果的行数，offset添加偏置，也就是说可以从任意行开始查询。
select …
union
select …mysql> select *from books;
+---------+-----------------------+-----------+-------+----------+------------+
| book_id |title | author_id | genre | pub_year |isbn |
+---------+-----------------------+-----------+-------+----------+------------+
| 1 | The end of the affair | 2 | novel | 1938 | 0099478447 |
| 2 | Brighton Rock | 3 | novel | 1938 | 0099478471 |
| 3 | The Quiet American | 1 | novel | 1955 | 0099478393|
| 6 | The End | 1 | novel | 1939 | 0099478472 |
| 7 | Python | 1 | novel | 1970 | 0099478473 |
+---------+-----------------------+-----------+-------+----------+------------+mysql> selectauthor_id,count(*) as total from books group by author_id having total>1;
+-----------+-------+
| author_id | total|
+-----------+-------+
| 1 | 3 |
+-----------+-------+
1 row in set (0.00 sec)Join语法
table_references:
table_reference [, table_reference] …
table_reference:
table_factor
| join_table
table_factor:
tbl_name [[AS] alias]
[{USE|IGNORE|FORCE} INDEX (key_list)]
| ( table_references )
| { OJ table_reference LEFT OUTER JOIN table_reference
ON conditional_expr }
join_table:
table_reference [INNER | CROSS] JOIN table_factor [join_condition]
| table_reference LEFT [OUTER] JOIN table_reference join_condition
| table_reference NATURAL [LEFT [OUTER]] JOIN table_factor
| table_reference RIGHT [OUTER] JOIN table_reference join_condition
| table_reference NATURAL [RIGHT [OUTER]] JOIN table_factor
join_condition:
ON conditional_expr
| USING (column_list)在MySQL中，CROSS JOIN从语法上说与INNER JOIN等同（两者可以互相替换。
cross join 相当与笛卡尔积。
Left join：匹配左侧，即使右侧没有匹配项，也显示。
Right join：匹配右侧，即使左侧没有匹配项，也显示。
例子，使用 on expr 将两个表连接起来
mysql> select concat(author_first,author_last),title from authors
-> left join books onauthors.author_id=books.author_id;
+----------------------------------+-----------------------+
|concat(author_first,author_last) | title |
+----------------------------------+-----------------------+
| J.K.Rowling | The end of the affair |
|GrahamGreene | TheQuiet American |
|GrahamGreene | TheEnd |
|GrahamGreene |Python |
+----------------------------------+-----------------------+
4 rows in set(0.01 sec)例子，使用using（column_list），将两个表连接起来
mysql> select concat(author_first,author_last),title from authors
-> left join books using(author_id);
+----------------------------------+-----------------------+
|concat(author_first,author_last) | title |
+----------------------------------+-----------------------+
| J.K.Rowling | The end of the affair |
|GrahamGreene | TheQuiet American |
|GrahamGreene | TheEnd |
|GrahamGreene |Python |
+----------------------------------+-----------------------+
4 rows in set(0.00 sec)故意在authors中添加一个，无法匹配的行。
insert into authorvalues (10,”altman”,”wang”,”CN”);例子，左查询
mysql> selectconcat(author_first," ",author_last) as name,title from authors leftjoin books using(
author_id);
+---------------+-----------------------+
| name | title |
+---------------+-----------------------+
| J.K.Rowling | The end of the affair |
| Graham Greene |The Quiet American |
| Graham Greene |The End |
| Graham Greene |Python |
| wang altman | NULL |
+---------------+-----------------------+
5 rows in set(0.00 sec)Update
Single-table语法：
UPDATE [LOW_PRIORITY] [IGNORE] tbl_name
SET col_name1=expr1 [, col_name2=expr2 ...]
[WHERE where_definition]
[ORDER BY ...]
[LIMIT row_count]Multiple-table语法：
UPDATE [LOW_PRIORITY] [IGNORE] table_references
SET col_name1=expr1 [, col_name2=expr2 ...]
[WHERE where_definition]UPDATE语法可以用新值更新原有表行中的各列。SET子句指示要修改哪些列和要给予哪些值。WHERE子句指定应更新哪些行。如果没有WHERE子句，则更新所有的行。如果指定了ORDER BY子句，则按照被指定的顺序对行进行更新。LIMIT子句用于给定一个限值，限制可以被更新的行的数目。
Load
LOAD DATA [LOW_PRIORITY | CONCURRENT] [LOCAL] INFILE 'file_name.txt'
[REPLACE | IGNORE]
INTO TABLE tbl_name
[FIELDS
[TERMINATED BY 'string']
[[OPTIONALLY] ENCLOSED BY 'char']
[ESCAPED BY 'char' ]
]
[LINES
[STARTING BY 'string']
[TERMINATED BY 'string']
]
[IGNORE number LINES]
[(col_name_or_user_var,...)]
[SET col_name = expr,...)]在导出文件的过程中，支持配置字段分隔符，包裹符，和转义符。和配置行（记录）结束符，和起始符。
load data infile ‘data.txt’into tabledb2.test
fieldsterminated by “str1”
lines terminatedby “str2”
ignorenumber lines；每个fields由str1隔开，每行由str2结束，自动忽略前n行。
load data infile 是
select column1,column2,…columnN intooutfile “/tmp/result.txt”
fields terminated by “str1”
lines terminated by “str2”
from test；的补语。