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[400.12 --> 403.20] but some properties of this information should not be changed,
[403.24 --> 405.52] like the history of the values.
[405.84 --> 408.70] If you want to scan over a whole history of the values
[408.70 --> 412.64] and you maybe have a use case where you have to look back
[412.64 --> 416.62] what was the state of a time, this history will not change.
[416.62 --> 419.94] So that's also a property that maybe you want to keep immutable.
[420.68 --> 422.68] And also the database,
[422.98 --> 426.94] maybe you want to have an extra layer of protection from the database
[426.94 --> 431.40] so that you don't accidentally change and damage this information.
[431.82 --> 434.68] I remember when I was working on some standard databases,
[434.86 --> 435.64] this common database,
[436.04 --> 441.02] there's this feeling when you do delete too much records from the database
[441.02 --> 442.52] and suddenly you feel that,
[442.74 --> 445.50] oh, how can I get out of this situation?
[446.40 --> 448.68] And immutability here helps a lot.
[448.90 --> 450.50] It gives you this peace of mind,
[450.58 --> 452.58] but there's also much more to it.
[452.86 --> 452.90] Right.
[453.26 --> 456.30] Let me try to sort of state that back to you,
[456.42 --> 457.76] but based on the way I understand it.
[457.80 --> 460.22] So when we're talking about immutable data, right,
[460.22 --> 463.08] let's just remove the database aspect of it for a second.
[463.18 --> 464.34] When we talk about immutable data,
[464.40 --> 467.02] we're talking about what is the state of things?
[467.76 --> 469.64] What is the reality of things right now?
[469.64 --> 471.50] Or at the time I choose to record this data,
[471.58 --> 475.06] be it on a piece of paper or electronically in a database, whatever, right?
[475.26 --> 477.22] What is the state of the world right now
[477.22 --> 478.76] at the time I'm writing this piece of data?
[478.88 --> 483.70] So if currently it is 50 degrees Fahrenheit at this hour, this minute, right?
[484.04 --> 485.64] And in another hour, right,
[485.68 --> 488.90] if the temperature rises by 10 degrees and now it's not 60 degrees,
[489.26 --> 490.86] you're not changing the past.
[490.92 --> 492.78] You're not changing when it was 50.
[493.06 --> 495.22] You know, you're basically adding a new record saying,
[495.22 --> 499.98] okay, another snapshot of this data means that at this hour,
[500.08 --> 501.48] now it is this temperature.
[501.66 --> 505.84] So it's almost like you're dealing with sort of an append-only logging kind of situation
[505.84 --> 510.14] where at any given time, you're able to sort of go back in history
[510.14 --> 513.94] to figure out what was the state of the world at this particular time,
[514.08 --> 515.46] this particular point in time.
[515.46 --> 519.28] But for, which is, I can see why sort of a,
[519.36 --> 521.90] this creates some sort of a trail, a log, auditability,
[522.04 --> 524.56] that kind of things and see, okay, well, how is this thing changing over time?
[524.64 --> 525.32] Who changed it?
[525.40 --> 526.60] You know, why, whatever, right?
[527.16 --> 531.22] So that applies to this particular use case whereby in most cases,
[531.22 --> 534.88] what I'm used to is give me the current temperature, right?
[535.20 --> 538.40] Whether I ask for that an hour ago or an hour from now,
[538.54 --> 540.72] I'm asking for the current temperature.
[540.80 --> 541.62] Give me the current temperature.
[542.12 --> 545.44] So what you're tracking behind the scenes, multiple versions of it,
[545.46 --> 547.12] that's kind of your business.
[547.32 --> 550.22] But sometimes I just want whatever the current value,
[550.32 --> 552.90] however you determine that, I want whatever the current value is, right?
[552.90 --> 554.84] So those are slightly different use cases.
[554.92 --> 560.00] So it seems to me that immutable databases are about keeping history of things, right?
[560.00 --> 564.28] Not about sort of being your own, almost like your primary database.
[564.40 --> 566.06] Like if I'm building a weather app, right?
[566.30 --> 569.60] I may want to see, right, what the historical value is.
[569.68 --> 574.06] But if we change that a little bit and add, say, a financial services app or something,
[574.06 --> 576.30] I may not for a bank, for example, right?
[576.64 --> 580.16] When I can see my account balance over time,
[580.78 --> 585.32] and every time this entry was sort of a, every time my account is changed, right?
[585.48 --> 589.22] Maybe a new purchase or a debit or some sort of deposit.
[589.22 --> 591.06] I'm tracking that over time.
[591.58 --> 594.02] But at any given time, I want to know what's my current balance.
[594.10 --> 595.58] Can I buy this thing or not, right?
[595.80 --> 597.22] So there are different use cases.
[597.38 --> 599.34] One is not supposed to replace the other.
[599.54 --> 600.54] Do I understand this correctly?
[601.08 --> 602.30] In a sense, yes.
[602.76 --> 606.22] So basically, this immutable database is like a water over time.
[606.22 --> 608.50] But it also contains the most recent state.
[609.02 --> 611.90] Like if you want to check the balance, your current balance,
[612.28 --> 614.20] it will still be inside this database.
[614.20 --> 618.46] So there is still a use case as a primary source of information.
[618.62 --> 623.94] But it's actually more about protection against some kind of tempering with the history.
[624.76 --> 629.00] So if you want to make sure that the current balance is the true information,
[629.44 --> 635.16] how can you be sure that someone did not do some kind of change in the history,
[635.58 --> 636.38] alter the data?
[636.76 --> 639.78] How can you be sure that the current state is actually valid?
[640.24 --> 643.42] Let's have a use case where there is a banking application.
[643.68 --> 644.86] Like a simplified use case.
[645.04 --> 645.72] And there is a user.
[646.34 --> 650.84] If you want to check your current balance, you open this application, check the balance.
[651.06 --> 652.12] Then you do some purchases.
[652.60 --> 653.92] And then you check the balance again.
[654.50 --> 658.78] So you intuitively check if this thing match.
[659.44 --> 663.98] So if the previous state, previous balance, and the price that you have to pay,
[664.22 --> 665.08] if this all matches.
[665.66 --> 667.96] If it doesn't match, you start being suspicious.
[668.56 --> 669.40] Something is wrong.
[669.78 --> 676.24] And immutability also and verifiability can be used to actually make sure that not only
[676.24 --> 677.40] the user can do this.
[677.60 --> 679.32] So you remember the old state.
[679.62 --> 680.82] You know the current state.
[680.90 --> 683.82] And you can somehow check if this is consistent.
[684.64 --> 689.66] And immutability here, and especially in NimiDB, gives you tools, cryptographical tools,
[690.20 --> 693.42] to make sure that actually the database did not fly to you.