AliSQL: [Feature] Issue#6 SQL FILTER

Summary:

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This feature limit queries of SQL which contains key words.

Only SELECT, UPDATE, DELETE can be limited.

Usage:

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add a rule limit SELECT:

SET GLOBAL sql_select_filter = '+,{CONC},KEY1~KEY2~KEY3...';

keys seperated with '~'

example: SET GLOBAL sql_select_filter = '+,1,t1~t2~t3'

SQL contains 't1','t2','t3' can only have one conncetion at the same time

sql_update_filter and sql_delete_filter for UPDATE and DELETE

show rules:

SHOW SQL_FILTERS;

select * from information_schema.sql_filter_info;

result example:

TYPE    ITEM_ID CUR_CONC        MAX_CONC        KEY_NUM KEY_STR

SELECT  2       0       0       2       +,0,a=1~a=2

SELECT  1       0       1       2       +,1,a=1~a=2

delete rules:

SET GLOBAL sql_select_filter = '-,ITEM_ID1,ITEM_ID2,.....';

delete all rules:

SET GLOBAL reset_all_filter = 1;