mysql - At what number of columns should you make another table? -


i had table reached 20 columns.

i find each 1 necessary since it's "project" table, , project has columns indicate stuff such when created, when updated, id, started it, finished it, metadata such keywords, content of project itself, brief description , other stuff.

i happy table, browsed questions through stackoverflow , saw stuff "your table should never have more 10 columns" , suggestions if case, should split table smaller ones.

following stackoverflow's advice, split table 2 tables, i'm finding more complicated manipulate. now, when each project created, have create 2 new records, each 1 each table. have handle errors on creation of either record, means if creation of record on second table fails, have yet query rollback creation of first record. data retrieval , record deletion has been made more complex, since have on 2 tables.

i'm using sails.js framework, , trying use associations, find it's pretty same, still have repeat tasks each table.

is worth split table smaller ones if gets big? or should keep 20 column table? project new, not online, don't know performance. i've never understood associations/joins or databases in general, in, i've never understood why people it, so, benefits?

keep 20 column table, honest 20 columns not lot considering 5 columns taken, tell, when (created, edited) , id.

there other considerations when designing database table, number of columns should not priority. can think splitting multiple tables when have performance issues keep table. go 40 columns , still should not care.

the person said never more 10 either talking performance issues can addressed, or specific case made difference or has strange "standards".

but should understand database design, see how design tables better, make tables many fields want long respect normalization rules


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