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mysql - The Nested Set Model Unlimited depth? -


http://mikehillyer.com/articles/managing-hierarchical-data-in-mysql/

in article above wash shown table:

1 ( electronics

2( parent 3(some item )5 ) 10

15( parent 16( item)17 )18

) 20

i don't understand how can unlimited depth if limits set 1 20 parent , depth betwen numbers limited can see, when create table , insert many records, , don't know depth be, need set left 1, , right 1,000,000 ??? have conditionally unlimited depth? o_o

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http://mikehillyer.com/articles/managing-hierarchical-data-in-mysql/

in article above wash shown table:

1 ( electronics

2( parent 3(some item )5 ) 10

15( parent 16( item)17 )18

) 20

i don't understand how can unlimited depth if limits set 1 20 parent , depth betwen numbers limited can see, when create table , insert many records, , don't know depth be, need set left 1, , right 1,000,000 ??? have conditionally unlimited depth? o_o

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or how can insert records without knowledge of how many parent or children be? going left right how can this? beginning id 1, values of left , right??? – mister php jul 6 '12 @ 22:31
    
can explain??? – mister php jul 6 '12 @ 23:21

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