database - Mysql- Single Sequence Table for all Tables -
i have created database in mysql firebird database. in database there common sequence table(common_id) generates sequence tables (45 tables in database). tables
table1 = sequence (id auto-increment)-the common sequence table table2 = process (sequence, process_number(unique), category_name) table2 = tasks (sequence, barcode(unique), process_number(sequence process table), product_name)
this database has more 600,000 records. 1 "process" can have many "tasks". questions are: relationship should between "sequence" table , "process/tasks" tables? relationship should between process table , tasks table? how insert in "sequence" table , use "id" in other tables?
this first question , new databases, apologies mistakes.
the relation between sequence , process 1 one, relation between sequence , task 1 one (and same every other table uses sequence table in way). 1 side of relation (process resp. task) don't need exist.
the relation between process , task 1 many.
your insert like
insert sequence values (0); insert process values (last_insert_id(), ....); insert sequence values (0); insert task values (last_insert_id(), ....);
by way, in data model table process has 2 primary keys now. might better data model when use process's sequence foreign key in task.
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