📄 ps_10nestset.test
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################################################ ## Prepared Statements test on ## "nested sets" representing hierarchies ## ################################################# Source: http://kris.koehntopp.de/artikel/sql-self-references (dated 1999)# Source: http://dbmsmag.com/9603d06.html (dated 1996)--disable_warningsdrop table if exists t1;--enable_warnings# "Nested Set": This table represents an employee list with a hierarchy tree.# The tree is not modeled by "parent" links but rather by showing the "left"# and "right" border of any person's "region". By convention, "l" < "r".# As it is a tree, these "regions" of two persons A and B are either disjoint,# or A's region is completely contained in B's (B.l < A.l < A.r < B.r:# B is A's boss), or vice versa.# Any other overlaps violate the model. See the references for more info.create table t1 ( id INTEGER AUTO_INCREMENT PRIMARY KEY, emp CHAR(10) NOT NULL, salary DECIMAL(6,2) NOT NULL, l INTEGER NOT NULL, r INTEGER NOT NULL);prepare st_ins from 'insert into t1 set emp = ?, salary = ?, l = ?, r = ?';# Initial employee list:# Jerry ( Bert () Chuck ( Donna () Eddie () Fred () ) )set @arg_nam= 'Jerry'; set @arg_sal= 1000; set @arg_l= 1; set @arg_r= 12;execute st_ins using @arg_nam, @arg_sal, @arg_l, @arg_r ;set @arg_nam= 'Bert'; set @arg_sal= 900; set @arg_l= 2; set @arg_r= 3;execute st_ins using @arg_nam, @arg_sal, @arg_l, @arg_r ;set @arg_nam= 'Chuck'; set @arg_sal= 900; set @arg_l= 4; set @arg_r= 11;execute st_ins using @arg_nam, @arg_sal, @arg_l, @arg_r ;set @arg_nam= 'Donna'; set @arg_sal= 800; set @arg_l= 5; set @arg_r= 6;execute st_ins using @arg_nam, @arg_sal, @arg_l, @arg_r ;set @arg_nam= 'Eddie'; set @arg_sal= 700; set @arg_l= 7; set @arg_r= 8;execute st_ins using @arg_nam, @arg_sal, @arg_l, @arg_r ;set @arg_nam= 'Fred'; set @arg_sal= 600; set @arg_l= 9; set @arg_r= 10;execute st_ins using @arg_nam, @arg_sal, @arg_l, @arg_r ;select * from t1;# Three successive raises, each one is 100 units for managers, 10 percent for others.prepare st_raise_base from 'update t1 set salary = salary * ( 1 + ? ) where r - l = 1';prepare st_raise_mgr from 'update t1 set salary = salary + ? where r - l > 1';let $1= 3;set @arg_percent= .10;set @arg_amount= 100;while ($1){ execute st_raise_base using @arg_percent; execute st_raise_mgr using @arg_amount; dec $1;}select * from t1;# Now, increase salary to a multiple of 50 (checks for bug#6138)prepare st_round from 'update t1 set salary = salary + ? - ( salary MOD ? )';set @arg_round= 50;execute st_round using @arg_round, @arg_round;select * from t1;drop table t1;# End of 4.1 tests
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