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let's try this one called Tyll.
2,585.93
2.79
Well, maybe I want to just find the titles that have a Y or an I in here,
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5.04
but I also don't know if it's one L or maybe two L's, for instance.
2,593.76
3.933
Let me go back and try this.
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1.167
I'll say SELECT, let's say, "title" FROM "longlist" WHERE my "title" is LIKE--
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8.07
I know it begins with a T. I don't know if this is a Y or an I.
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4.56
And maybe I know that it has maybe one or two characters after it.
2,611.49
4.62
So I'll try this one.
2,616.11
1.5
Now I have three underscores, single underscore.
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3.21
So match any book title that has T and then any three
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4.38
individual characters after it.
2,625.2
1.8
I'll hit Enter.
2,627
1.29
And I'll see I get back Tyll.
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2.01
This is the only title that has T and then three characters after it.
2,630.3
5.7
I could try to get better with this.
2,636
1.69
I could say maybe I'll accept five or six characters like that.
2,637.69
3.29
Hit Enter.
2,640.98
1.05
And I'll see-- whoops, I didn't compute my query here.
2,642.03
2.467
Let me just try it from the top again.
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1.583
I'll say SELECT "title" from "longlist" where
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2.79
title is like, let's say, T-Y underscore, underscore,
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3.9
underscore, underscore.
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1.2
Hit Semicolon.
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2.82
And now I get no matches.
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1.46
So there is no book in the database that has T-Y
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3.84
and then, let's say, three or four underscores for any character after it.
2,662.09
6.05
OK.
2,668.14
0.69
So this covers our use of LIKE, but let's
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4.08
keep going and building more complex conditions
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2.22
to find even more answers to questions we have about this data over here.
2,675.13
5.31
Let me think what we should show next.
2,680.44
3.09
We've seen LIKE.
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1.26
We've seen some compound conditionals.
2,684.79
2.07
Well, let's go back to trying to find books that are in a certain year.
2,686.86
4.53
So we saw earlier we had this kind of query.
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3.15
We could say SELECT "title" and "year" FROM, let's say, our "longlist."
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6.27
Now I can try to find those books that are written or nominated
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3.57
in 2022 and 2023.
2,704.38
2.61
But let's say I want to go further.
2,706.99
1.89
I want those from 2019 to 2022, a span of multiple years here.
2,708.88
6.25
So I could try it like this, WHERE "year" equals--
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3.86
let's go ahead and say 2019--
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2.31
OR "year" is 2020 OR "year" is 2021.
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6.86
And let me make a new line again.
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2.22
OR "year" is 2022 Semicolon.
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5.81
And before I run this query, let me ask our audience,
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3.75
what strikes you as being not very well designed about this query?
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4.97
What could I be doing better here?
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2.65
So I'm seeing maybe one improvement is that I don't need to write out
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5.09
OR "year" is this, OR "year" is that.
2,752.65
3.3
I could probably do better with this.
2,755.95
1.95
And let's introduce some new keywords for working
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2.73
with ranges in terms of our conditions.
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3.61
So here, we can see some new operators to use.
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4.22
We have this greater than sign, this less than sign,
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3.99
greater than or equal to, and less than or equal to.
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2.91
And we can use these to build ranges inside of our queries to say,
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4.44
I want something to be greater than this number or less than this number too.
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4.83
And we can combine these with AND and our OR
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2.55
we saw before to get back in this case some set of rows
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4.26
that match what we intend to find.
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2.79
So let me go back and try some of these out.
2,794.23
2.22
I'll try to improve the design of this query.
2,796.45
3.39
Let me first run it, and we'll see we do get back 2019 to 2022.
2,799.84
6.51
But I could probably do better.
2,806.35
1.63
So let's try using our new operators here
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2.78
that can give us some range capabilities.
2,810.76
2.61
I'll say SELECT "title" and also SELECT "year" from "longlist."
2,813.37
6.42
But now I want those rows where the year is greater than or equal to 2019,
2,819.79
7.29
and the year is less than or equal to 2022 Semicolon.
2,827.08
6.3
I'll hit Enter.
2,833.38
1.57
Notice I'll get the very same results.
2,834.95
2.16
So I get all those same rows.
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1.91
But now my query is much smaller.
2,839.02
2.68
It's making use of these range operators I've seen so far.
2,841.7
4.64
I could even further improve this.
2,846.34
2.59
I could make this a little better designed to.
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2.45
Let me go back to some slides and show you we could use these keywords
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3.21
BETWEEN blank AND blank, where this can be some condition
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4.92
or some number in this case.
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1.72
I could say between, let's say, 2019 AND 2022.
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5.09
This is inclusive.
2,866.32
1.42
So if I say 2019 AND 2022, I'll get back a query that includes 2019 and 2022.
2,867.74
8.54
So let me try this one.
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1.62
I'll go back over here.
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1.23
And I will now try SELECT "title" and "year"
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5.04
from "longlist," WHERE the "year" is between 2019 AND 2022.
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8.2
Same results now, which is a different way of writing this same query.
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5.62
Now what else can we do with these ranges?
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3.13
Well, as we've said before, these books actually have some ratings involved.
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5.36
These ratings are crowdsourced from Goodreads,
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2.55
a site you can review books online.
2,909.03
2.37
And I want to find maybe the books that have a rating of 4.0 or higher.
2,911.4
4.17
Well, I could do that now with my ranges I could say SELECT "title" and "rating"
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5.7
from my "longlist."
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1.74
And I could say WHERE the "rating" is greater than 4.0 Semicolon.
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5.91
I'll hit Enter.
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1.02
And I'll see now only those books that have a rating of 4.0
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5.16
or higher like this.
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3.56
I could even combine conditions.
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2.31