Save function is hybrid function of insert and update, if the row exist then save will update the row, if it doesn't exist it will insert the row, which is very useful thing in many cases
save insert the relational data also, which update and insert are not able to
and update function also don't work as it should, and issue is closed because no answer from the reporter
because save does both job and updates and inserts relational data, i started using it as replacement, but issue arises when you have system in which multiple users are trying to insert data concurrently,
for example, i have serial number logic for invoices in my application, where they will get assign the same serial number, if the other user have already inserted(which i check explicitly) the data with serial then the second user will get new serial number and id making it new row with unique primary key entry,
now here are two issues, let's say two users submit the form same time, and both request hits the same time, for both save checks if database has entry with this primary key or not, and database have no entry yet, it forms the create query for both request, one get's written and other get's error duplicate primary key, now this issue can be handled using try catch,
but when both query arrives and for some reason second query'd save check is still not completed, in mean time first query have inserted the data using save, now save says there is entry in the database, and it forms update query, and it fires the query which overrides the old data, so where there should be two rows of data, now there is only one, issue is already open and closed without any answer
below table explains the both issue with step and time stamp
I liked this solution, in which we pass extra optional parameter allowedOperations: ["insert", "update"]for allowed operation, if allowedOperation is mentioned then save will only perform that operation, if anything haven't passed, it will work as normal save,
i have done the changes for this solution to work, i which insert is working fine, but update is not working as expected, i am not able to run the typeorm repo locally, what i did was made changes build package, and replaced that in node_modules typeorm in my project, if you can guide me what i am doing wrong or how to run typeorm locally, i was only able to find test, there are sample folder, but no documentation on how to run them, implementation link