Digging Into Django's Migrations

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Digging Into Django's Migrations
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An in-depth look at Django's new migrations framework, explaining the component architecture, highlighting issues with multiple database backends, and showing how management commands typically get routed through the software.
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images but I am previously so the pattern of demand what and the author staff the research and the cost of the from the name of relations and cases of sequentially at the point where I am so the to that a staff and general difficult design decisions in the use of for the 1st time so this talk is about is essentially the history of staff like him about how it developed and then what became of language was gender migrations and importantly how migration that so what is and isn't were not implemented and so the pixels in the issues that I have crossed and identical Mr. with an idea about how supplement to not be scared migration is that it if 1 of these injections of newcomers agenda in the last couple of years I think and it's most likely of a jumbo about an incident accommodated that's is something that is very computer science the which means very difficult and sometimes the lecture and explain to you in this and that is a cross so has just mentioned
and I to everything would come in US this is the 1st looking very long and start instead of a stage and I have I believe anyone would to give the presentation migrations the US and I have put have 1st hand and think that you and things in your head is visualized slope that it's it's interesting to have 1st slide deck and 1st infectious that is very similar in some way so we have the value and differences but
after this time of the past and user deliberations I that would and didn't really uh those moments as a component of the vector and the and in the end he into migrations south became so the intended apologize and provide an editorial when you need to install download the to still sound and then you can go and from time thousands of OK if we use some of the capacity of the new players in the field and let widening the dogs land which use policies and finally use as you learned its elements and how think about
so and through this yourself it's South was initially launched in August 2008 and it was launched in fact from the
2nd to the right window this building here but this is the 2nd block included popular which it should be very lovely place to go from and I was looking the time for the agency called Twitch books uh who are so some of the major sea in Oxfordshire and they have for some reason from offices in a country states um so this this administered have indicated on the length of the island like from the large amount it's fantastic having a some of the 1st versions were mentioned and sort of made for a single projects and at the time making a very simple sort of CMS for a customer a simple mentally complicated and previously the company method was we have directly from single fails we run the single files and we just keep number our heads that includes you we have a common a number that we remember the number of the number and then at some point we signed on and to me in the that Persian like over time and said so that we want to know if so this is and this is something that something that the system and out of that and all a curiously estimate was that he was working with the same company the previously launched from this is that same thinking migration is so that his version of that and it's shockingly similar so I think we can improve both of them and that lands and immigrations was my see well you of was well is the noise not from an American exodus Chinese allusion done that then the positively and it notice I that to study the countries of by itself and is quite popular time and they actually found out popularity and indeed there is in some respects Saturn competitors of like as you can see here the times been admired releases to the prize of the pressures of having other things didn't get out of it the the last 2 years after this point and before the segment went all those little detection you could have been go way south don't to touch and feel this that this that through all this and then I believe it was migratory they came in with the idea of was that it was his actions storing state and the licenses can extract from them and its number 4 um returned by the electrical coming you and annotation implantation to like sort of paradigm of and the some of salicylidene only appears no around point for the number 1 and number the nominations at least 11 . no list of about compatibility which I'm very proud of own life migrations the 1st version that really single and that sort of thing family that saying things like different operations most sections of the dead so that becomes more than you can simply don't change will run so see migration and then migration testing the method of
2009 2 thousand and 2010 and approachability and the answer is included in this is for the years ago um in the short term the 2nd 1 will be released so as all of 2010 here and is a is wrong and this is a period where the self becomes pretty much what is required it mostly because see that the issues were missing holes but it's good enough like the big hole also coming in people journalism work around the issues and it's not perfect that
it does the job and then between 2010 and 2013 there's no release that no major releases and because of the long
gap that was that you know that I recognize the hours in lot work as freelance as reasoning high stress um and then from the mid 2013 tank on Europe about unreasonably I essentially is a collection of bugfixes in a few new features of occluded years at the same time of the image and the Kickstarter which funded the remainder of the work and to this day and so I ask for 2 and a half thousand pounds I got to see it almost 18 thousand pounds I'm very grateful to everyone who contributed many them here I show you a few but and if if you gave please come see me I would get it that for you again uh this essentially funded the work in younger notices that I could go down to 3 days a week my generated I could then work quality week on gender and that down and then the the of the mysterious times a good approach that might but was being paid to work on it like this the county time you can have a sort of fixed times and we write code review bands creative people as agenda fellow like and the patterns of having like assess enough time but we do this stuff it's it's actually invaluable for this and then examples of lone pair with me working on generations and so I was working on staff and then a considerable
work on last month I mentioned only summoned goes Macedonian wasn't released enough the correlational whose work a gentleman has this happened when the world is essentially just nobody but for would want to change which is a way of having migrations that exist alongside China migration so both in the south of its 1st applications ready but to provide efficient and fill factor migrations directory meaning ship that with both migrations and the generation is a big part of our to operate because you know
about so that in 2010 and some of those are also important when real soon now and I right through the amount suggesting that cell should be in Jericho and the people I mean like take a lot relatives coming and and you can do to include all of the moon is made of knowledge staff a of so that would be good for this new version migrations include handling this the focus part the studies and this point and at this point I have less than 5 years of of set a and set issues like and maintain only the sea from that is the issue tracker essentially 0 but public awareness and so you know the promotion of in the continuous stream of issues about mostly they can convince yourself was absolutely terrible because of all we is the some of other as fantastic and so the activity like this stuff and so on with this was 1 of the things that come to is that it's a method to extraction of who's using January of doing and so the national self-selecting the final trackers and so it is that I was thinking about you know how to structure this meant you so the should
have been invented 10 but by the time it was I have 2 different components so as the key about the sort of situation the environment itself grew up in the competition of of different ideas of persist and so on that day the common migrations looks and think that was in the back and where you extract things that kind tables ruling tables change things that you tractors out across the basis of gender that this will queries using the term we should extend that do a different level of article and that's the have a of unique constraints and identical about gender crossing back and that's so the key thing the South as well it's doing different versions of the models is that of different migrations the versions of models so we have a detection has been drawn between the that you'll see in a bid not familiar with the video and found that it makes plan you will back only versions of models of memory and runs migrations on so it reflects happened look at a time you made it this agenda the suppose this is modeled after which are then suggests is a lot of hand patches in his work as a Michael was carried through that modulus make that have China from the 1st class of people for having come to the model versions of inhabitants of and the same time so the this of self to itself to users online media in China and then the best you face and better migration management of it so that sounds good and that occurs at some point in the conservation of mutual man code of something that distance and things that exist in the country and what they that was of use of it in and out the answers in the things that are essential to development should be in the agenda the patterns in the frame of his employer and so the plan kind of changed you know
let's just in so the 2 components that migration handling in the user interface suddenly the known search and so on and so this indicates that at this point and I think optimistically opposed that the back of the same kind of migration cement from 1 . 6 and the code for this does exist it is the shopping slinky functional and south to release it's not states just interest isn't Wilson may since gender source code to ban full and there's a whole innovators buttons on a mapping that takes a code for migrations transformed into certain things and diamonds in the South you actually a sentence that had the functions make it work and manages to run migration from before knowing how it works and how they actually patentable McClellan Phillips officially 11 point 7 liters the outline the shrine around a little so complex that it is definitely a lot of structure because I was suggesting back uh said so the plan
was to focus in work on gender 7 and unfortunately I can do this out but these are the 4 mentioned softening . mil their migration patterns and use it as a solution you can have those properties of migrated is will sort of secondary ones have to have and 1 1 7 rounds and use the full power of framework so cannot are close to the Python that is an option to you about this a higher burden of maintains that the APS this and basically fuckin how you and things please about me because you know I'm happy to have people will start to number 7 it that makes the easier it was and you have sort of changes in the different parts so it's
not really moving south and a giant like the common knowledge of the conditions of the giant is a bit of a common misconception of the because of the economy is is that I'm kind migration is a planning framework I about facts and the cohesins artifact of the new stuff all the ideas of himself is entirely written very much and so it's not just a simple so this is the local redesigning mothers whose work includes and designs it in south along and then changing so the clinical sort of structure hydrogens worker making modular making reusable has received a bit you can take part in patients in the units of steadily from generation I
don't have to keep that separation of the so I should say my initial plan their gender still surprise the earliest changing from migration and if you want to you can just use student and never migrations library that somebody could do and I can play with these congerie language we have you have you have accessibility in China interface to changing scheme in a reliable fashion in transactions like that is that is code you can work on that if you want to say that we did not useful additions framework we have that too it's what you want to know if you have a constant the problem because of parts to do just we like much of the adaptive right and to be working so go through these different parts of the so no detail as he says about them since this is welcome to the abstraction earlier is a piece of code that takes the idea of modifying databases when in DDL is called data that is a data definition language and as far as the standard every back in and and you can you collection of the minute you get 1 of them I have methods like model we have methods like at field the field remove field changing the together with kind of stuff and the people that do things uh the 2nd coefficients a separate from that is FIL be deconstructive which was later but this means is that you can take a few sort of the charter law firm key in Austin how you made you can take the field on the interest seam reliable flatly can recreated again a 2nd time before this you couldn't take a giant field and so realizing that model instances and most of the things I have stolen the instance variable but some of the world they started this so sigh . 1 2 . 5 actually invent the source code remains a powerful popular now the rule that checks that will further into that of which is horrific um but not surprising that many students out of the meaning of the word and and then later on Saturday and hold rules that well if you see chapter you this is you have to do this and then if you sort of customs that body field if invent medical staff field trip and that is essentially what is said OK you feel tell me how I make and the constructed just that formalized the political agenda and this is now a requirement number 7 for that play fields if you wish to migrations and however there are plenty docking do it's those examples mistakes and if you're inheriting from the humans on China only have many changes so that he wouldn't even genital so again if you have factors e-mail me your gender gardening about that as 1 of the few sort of in requirements of the body at the moment finally the so there are important to mention the 1st slide backwards to the separation and now new options so you can now make models live in different worlds and so insecure actually start from point 7 changed we cash to it sort of more furniture is much better last concept and now you can learn more than 2 different versions of maps with for the trees and so will the migration very designated different competition for every point in history will show you later and so we can easily have like for of the user model and address directly on the referent he's going to the right places every time migrations out a much more complex of course that removing perverse and there are 2 separate into operations which are the abstractions around the individual skin edited methods things like this right had a field revolvers so operations should and of the graph this sort of where the stretching out you have instead this what they need to have dependencies world how to results stuff had planned migrations that's come in that section the executive simply takes a plant and the load of the graph and runs it said that the takes a list of things around those not from the operations defined as well and actually can it won't at Princeton OK and it's going we detector most complex probably this is well takes your current state and the accommodation migration stating so intelligently comparison and let's applications that include lots and stuff and south of the 2nd and the state is the final part and say you don't care have a thing where travel working directly on those agenda models with migration styles it works on so much stripped-down version local state and because there somewhat varieties where they can work state quickly we can run through from nothing to and stayed in the hunt is a migrations and function of a 2nd global markets was changed changed its like statement electrical impulse and it's so he's right that's definitely not doing a show here so the
1st key so close and quantity is operations in state now these 2
to kind of get operations are declarative representation of changes feudalism migrations will see a big list of operations in a list of words that is higher than other migration I and the separation from the separation for this operation is how you have 2 messages for the backwards but operations to develop structure where the concept of eventually cause there was the backwards is simply the reverse of forwards the operations not work requirements operation additionally know what changes represent without database schools operation you can say the state what is on the state like and you know you can do it quick in memory changes so you have that animals of articles and his version of modelling and then we can render those out different versions was seen a bit quite and so the right to have is that we
have each state and operating texture in the state and internally memories migrations is keeping a state for every individual thinking operations in a fact and
migration is nothing more because of relations and so you can see here that in I said migration event into back on migration in fact this is how and then you scratch migrations command works it takes 2 operations is concatenates them in optimizing alive and then as a penny migration from items to see that that negotiations about the generalized framework for closure of operations innocent specific concept you could do and technically but that that sort of useful reasons in addressing name these
are the operation ownership with um there's confusion as you can see wasn't 1 of them that you might not know our own sequel in Python the bottom those are all operations that you can management follow like migrations and irreversible case feel free to add them methods and that we about and radical using the good ones at the properties and run python looks basically like an old staff that it take it you get 2 elements you get switch around that you get the words and you can do it like so much like this the migrations really content changes its for things like Langston procedures it's people it is the fact that you have to have a field of if you want it beneficial in a much more simplified migration from what is much more understandable and much less prone to model of missing certain different things the skin
and so as I mentioned fall is this sort of
abstraction over the duty of databases and this is pretty easy most things from our minerals suicide Americans and functionally sequel rights relevant half the database does not have support filtering tables and a single output linking drop tables you can have problems and that's it you got columns control and so Django staff and have a full emulation layer where if you accidentally interval icon do we make the computational inferences we compensate you over the head will be and indeed unintelligible and undergo and so if Mr. a cigarette migrations a really long it's politically having emulate functionality to others in general you should be doing heavy migrations on the polite it's meant for embedded systems development don't do serious damage than production at least it's a single access looking database software and the thing to mention is that scheme that takes giant demands of feels this oscillation of this could be due to the table lines and and sort of MIL drug it's the field as well into to take into towlines on column where this takes the domains and levels of and other objects and so it's a bit higher levels and that she didn't know how to no matter what the cost and he said well it's consumption something is who is actually the column of something comes along the south as sort of things like it is also where the public from consonant with exceptions from honest it is very simple
this basin for example of how to do cover changes and this is a convex non decision is to move a contentious in the and create a lot of fields but also from the office the edge and to see it the first one making the model it is possible instance the reading of version and the vector given current version of the of the in the migration framework for this and the 2nd 1 is having a field the possible because the fear of many parts and field for instance um that's and again Winston-Salem company construction which is called the so
the construction is this new thing what every few the construct and it returns in the arguments you passed the depends working it the place itself is hunter is made with those things in returns you give you the same kind of feel that this year the report of the it is it's a con without having things like copy of a copy of and not to say that the
so we use a simple if you want to use that describe the construction field you can refer to prefer things the 1st thing is the name of the field this field that 19 almost feel instances it's not example this is a field not handed to model so that it would not be different like all of you height saliva and the 2nd 1 is a fully qualified paths to the field so as you see here this is trying do models travels if you're custom field was only be like my act field stop custom fields so the 3rd element is positional elements we encourage you not to return these with a much less plausible across versions of you will feel the changes that have happened there and the 1st 1 is not so as you see here in this chapter will start happening here and I put into it so I can take these things I can do you it's that class will start at document and it we construct itself and that isn't really slowly and we will be using in which actors goes not merge kinds of field work because he needed by chlorophylls gender have 1 of those is not a problem the problem this is 1 of those and so in his work is constant the graph is this sort of more generalized
idea and if you know graph theory in mathematics it's directed graph and it is non cited as well as so stocks of the bad and it's a limit but information about the structure of the graph construction methods for traversing through at most importantly bound notes on opposite the most recent migration vary if we seem only for market means that you have merged to branches so the nice thing is that China migrations can because an explicit dependencies on parent in something that they need to be merged with the of to apps that into to the same pair of that must be a merge and then you can immediately quickly tell you and the room selection gives you the 1st migration react effects of Woodstock and they have planning so you can say I want to get to the knows it will give you an exact in the southern locations the wrong side dependencies to get the whole detection if you try and millions as and and the the circular and it was go so that the input and showing the cycle so you can break it and we wanted detect a full not like so dependencies this is the most of his work as well laughter events and it was it turns out that he's in and proxy objects and consumables because LEDs were really difficult and essentially the intelligence of
expertise the content from personal example but you got 3 at an that's coal mine at about 3 so that means that there a lot of them so that is out of the top of each column and then the roots of the animals and as it is here that you wanted to apply at about 2 units of a climactic coach the migration actually 1st in a settled at that point and so the load on the graph would tell you these things and and all of them from this the location database it sort of goes into a table we have gender migrations and out yet the Applied Signal migrations and use that information this program that is a feature that is in area here is that this is also support for having migrations replaced other sets of migrations so so if you answer should delegates of under migrations you can move and wrong and then the cadastral migration replaces all of these unintelligible intelligently spoken enough that if you have good way through that set it when submitting to copy hospitalization if you have a lot about the 2nd step is to reduce the tree so the advantages of here said and the commands script migrations makes sense falsely leads to the the extent and the 1 that I can get better version but at section 2 good start much themselves birthing way round phage 0 everything starts again the
detector is the most complex part of uh generations and what I've rewritten at least once during the beta phase agendas and so the best thing here is it takes
2 different states from Europe cognitive states so stating that thing was as high as that make yourself and trying in the current models so simple and it takes the final state migrations uh branches so that runs through the main memory goes up is that many comparison and then from back out of the set of operations president migrations and dependencies between migrations out of this stuff now the problem is that there is a very complex dependencies between migrations in initial Django simply being that was a symbol of changes made to the tables in the transaction and then declares foreign keys as well due to the end of the month so it can get a of stuff about point and because migrations forces you to have a separate component things on the development of you like we can't just leave 1 piece of land that was I the not the from a weeks in that case and so we have this very rigid dependency scheme where we go OK we have this for the points to hear Mr. because he was it 1 of the 1st and the 2nd was on the there is no complex we have 2 circular wings of foreign keys are said to have family to each other how do that in the and events in time that is different that's 1 come for that and so the fields at a suspect that into medicinal medicine and found the unaffiliated small so so this is with a set of another and then something like this and the of the difficulty is that
the 2 before the words that we take we take a break down the missile take to stay together OK here's a set of models that have change which is like you know intersection 1 of the things that is relevant to difference it and then added another set of his further change and then we take all those we don't have a rule that operations not able so generalized over and a big list the so in order to and then the the themselves have interdependencies at the foot of thinking will say on depend on the other hand me being created all things like having models I I depend on actually my saying maybe be moved 1st thing about I added the decoding goes through the lens of interest and to strengthen dependencies it pretty much always works now there's some very edge cases that along as bags of is answered because of the customer rules and you know this sort of nice of migrations that independence you live with the kind of dependencies that and there's a whole told how this works are good at some point and if you really want to find some not the codes to what the visual codebook so hard to work on that day ago the never mind you
don't come as part of this the optimizer takes a
set migrations annotated use millisecond flee was an effect and it can just return the same 2nd there like governing this elusive correction but the idea is that when your migrations and also during inspections of over like button section outputs a field for every function and then the 2 most commonly well you just got a little out her idea for again thinking and forced them to 1 of normal form so it doesn't
take you as preparations so that the age of because the ice steps pairwise is 1 of the longest and to so the moments and then it finds a pattern matches and the sample if he finds a account field and at the feeling OK those 2 and I could optimize away to nothing from the information which it finds an animal can feel the goes all those 2 glottal whether those who the same molecular was try so the idea is that we have the green 1 here is not model in the recognizer field so the middle as I did I feel the problem that was out this is this is too bad that we can get the optimized so that at end than the models match the film was not really good and and look at the beginning of the intervening operations make we call we can pass through the so for example if my field is out there and key to model and the middle 1 is quite that novel I can't push the affluent through traditional within the work of words as the only chance level can I pushed through the operations and can we can replace those 2 things down and restart thing again is he's living in loopy into the company has the resultant and this is where is not perfect as on the side of not reducing because that's a safe way we we know that what the full um 8 that can flow over a very very very complex topic and often available to implement such portrait it must have been nonetheless in this is somewhat couldn't empirical initial very good optimization so please help me this bit and I would like to have optimized even more intelligent even better optimizing that there's something that is missing is that it should be it should be catching on this in into the
design is 24 so I'm sure when
we do this and this is it's success as it says 1 thing and if you can't see it you can't the top section there is the actual constant migration the further market method I think it's just yeah it is just the create table like this migration is making 1 model posted um and so you have this China today and of and actions the top and then this giant chunk of frozen on the bottom we left there is that what's after tells is that everything migration down the entire history of the models to integrate integrated and so when remnants led us support of again and again that's reject wouldn't memory Amanda from that this is form of like notice is much bigger to see from the whole um but we don't have to say no model so we do it like that because of the use of the and the key thing we can do
here is for the energy of the memory running what happens here is that we can take a state and we can apply the migration operations in memory the states and this other the results
and so we can have known as any point in history I mean 1 from those and so we need that in the write that date to the previous operations in history and it's and it's it's almost as fast as the doing so critical throughout your commands
wrong to make models are make migrations which is you don't see migration derivation bonds and it's good for all that make migrations will make migration and was dependent migrations so you can pass on that plane enshrined in itself but if you have a migration even annihilations they were also uses only able to to make the migrations well that needs it knows it needs dependencies staff would you get immigration like that some of the work to didn't have consumers although migrations does and so does it take to 2 states often good detector so this leads to them to there's going to state from this and through going on from the project and then it takes the gate was succeeded big list the optimizer them so they have much shorter list and that passenger rights and the right as small class contagious Rob operations and right appetite of violent pretty decent like invented nice code that you could understand the person revenues of people understand migrations into human readable and unit edibles well migrate then
takes those different things it passes it is of those slogans as high but migrations slowly goes the distance from the start regarding and I'm in because because migrations around the 1 time of the transaction then runs operations individually the operation of the schools can editor individually and then modeled on this thing called the core the dimension is very simple it just says that that up losses applied all mothers on applied the modified and so just as a product and applied by on we still have the database individually multi dd to say that no database to run my great engineer late based of class I didn't just and do not allow migrate which is funded operation so you can individually tunnel migrations different databases so this sort of
the to address peer-review and is well what role like the designs on testimony will but like the real juicy that's here what we call the past like 3 months and so the 1st thing and and the like and for the rest of you know that this is levels now for those unfamiliar uh as a button your formal models then you can replace this case only sort the 1 is use a piece of cake and eat it it actually now this animal and inside gender was focus on point with try repairing active showing that on would turn your model which is fantastic and
it's dependency graphs so normally syntactic and assessing the setting of migration so dependent on his ideas change
this and then it goes crazy mineral
inside of and some of the German tablet which was the end of the phone is like the the graph would be something changes at 1 time and as you know it would fall by you time we kind held those parents like aspartame concerned that the British used them as a reference to like you know you see a different setting and so on In the case of we have the work ions in Django that support the staff and we just do a pretty good job and if you point depends exactly trial over but you can also get loops are those that if you present it to detect with among setting and then change it then there's no guarantee the resulting migrations all cycle free and independent of the that's
a big issue so the problem here is that we still runs in the apps and existence of 2 . org and so might measure about migrate just 1 of the in the 1st and then on the inside and this is fine article following keeping up so in different sections so the truce words doing the right thing he's migrate that into comedy that's meaning that we have to run migrations 1st so that their their their there around wearing of LabKey from from unrelated into migrated into but a limited 1st this decision we have is that you've got a phone keys from a disaster that this is a little problem because we moved political the and about 2 and a half migrations so you depend on those he migration so the and that this is not the way forward I would be like if you if it was around then it's horrible thing you have to like that was to product that you can do any changes at all so is a little annoying that adding migrations to existing at is very trivial even even wasn't like those by this amount of information on the page like other migration and then Django which replies occur in is like trying to revisit our listen criminals and we will not as applied to this puzzle before you the initial migration that it 7 ships migration spherical conjure up when you run like right that was about cells a 1st time going on there would that a family of my amendments and what even which is sort of conduct trunk you run migrations and it's an applies an improvement to another that uses it so that effect is only what we learn about the convicts rages we now should migrations what stuff cost about after that have positions along into the promising the under become mystical uh test systems in January we promise you that between every you will have the same starting state in particular the start loopy there that's great but the software seemed to be burning could do those of an initial data set which we played those with migration migration you can't makes up whenever you like in continental happens and so on to that persuasive in rental Latin value a valid test collection process where the collection that my and things we can't define and other investigators we call that the company how much income will that so that we do and what is that we have to have migrated greatest other test run we then redundant data into memory populated from the migrations and we learn from that for every test after flush so it's a little slower and notably you the test set and 3 times that and it turns out that in general the things that needed and if you have any issues with text assistance you those in our setting test eternal this is quite unique I actually I D 1 is wonderful to some tangent of speed of a slowdown as as required that I am perhaps was not tendered functional and in real downsizing migrations by throughout the meta actions and I forgot what will respect to existed in Thailand it during the beta phase the few around that time the intellect semi-automatic options like that so we have this thing where you can just make wearable with other thing what you some of the action that gives through 2nd round of while we support the fees for training the staff and the different countries as well and finally a consumables will things so proxy models of this thing we can have a model with the properties of normal and it has no titles and has no so and that is when the production code space lecture lecture on 2 objects and so that basically worthless but then there are tables in during with tool that you can find the to them and sending them around to the so the point from his answer just fate the paint about antiquing beyond the Vatican through some set of things as well if it's not and has property true then and stick this database parliament just leave it lying around sort of sort of the cultures I forgot about the change during the this proximal will be useless was even though the learning database of the article and foreign key to so is the bottom line you think about moving offers start with and that that that this this slide is written differently from was adamant that is still in that in the novel until the company I have migrations and please use them to form the final about like I am pretty confident because of Israel's so we have a very painful like 3 6 months of particles and fixing and movies hardening of that stuff out and limitations fantastic I hope you use them in the hope that you are going to collapse even if you need help others around like on us even in a meeting in order to developers and went to look at this painful transition period going to migrations over and we live longer future migration idea which
have been