在MySQL中，有特定语义的单词或者字符串比如delete，order等语法用词，count，sum等函数用词，我们把它称作MySQL保留字；
我们在数据库设计时，也就是在创建库表的时候，要避免使用这些字符串作为库表的某些字段名称，如果使用了，那么在sql语句中，要使用[]或者``以示区别，不然语句无法执行。
还记得那个update语句吧：
update dmz.award_inform set `Get`=1 where RoleID=290707225 and ZoneID=5;
在没加反引号之前，怎么执行都报错，而且是语法错，但语法能有啥啥错呢？
后来实在没办法联系了DBA的同学，他说给Get加个反引号试试。。。
之后我意识到sql规范的重要性，就挺突然的！
这里给大伙大致罗列下MySQL中的保留字：（阿里整理的）
action add aggregate all
alter after and as
asc avg avg_row_length auto_increment
between bigint bit binary
blob bool both by
cascade case char character
change check checksum column
columns comment constraint create
cross current_date current_time current_timestamp
data database databases date
datetime day day_hour day_minute
day_second dayofmonth dayofweek dayofyear
dec decimal default delayed
delay_key_write delete desc describe
distinct distinctrow double drop
end else escape escaped
enclosed enum explain exists
fields file first float
float4 float8 flush foreign
from for full function
global grant grants group
having heap high_priority hour
hour_minute hour_second hosts identified
ignore in index infile
inner insert insert_id int
integer interval int1 int2
int3 int4 int8 into
if is isam join
key keys kill last_insert_id
leading left length like
lines limit load local
lock logs long longblob
longtext low_priority max max_rows
match mediumblob mediumtext mediumint
middleint min_rows minute minute_second
modify month monthname myisam
natural numeric no not
null on optimize option
optionally or order outer
outfile pack_keys partial password
precision primary procedure process
processlist privileges read real
references reload regexp rename
replace restrict returns revoke
rlike row rows second
select set show shutdown
smallint soname sql_big_tables sql_big_selects
sql_low_priority_updates sql_log_off sql_log_update sql_select_limit
sql_small_result sql_big_result sql_warnings straight_join
starting status string table
tables temporary terminated text
then time timestamp tinyblob
tinytext tinyint trailing to
type use using unique
unlock unsigned update usage
values varchar variables varying
varbinary with write when
where year year_month zerofill
其实不论是否使用到了保留字，我们都需要规范我们的sql语句！~
以上。