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Jelly Fin: Should I use a query or scan?

Jonathan Irvin on August 28, 2018

Hey Dev.to, I have an endpoint where I'm trying to get a subset of transactions by date using between. When I run this, I get no results. Odd th...
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kip • • Edited

I think the problem is here:

ExpressionAttributeValues: {
  ':d': 'date',
  ':val1': year +'-'+month+'-01',
  ':val2': year +'-'+month+'-'+getDaysInMonth(month, year)
}

If you see the docs you can figure out how you need write the correct values for ExpressionAttributeValues, something like that maybe:

ExpressionAttributeValues: {
  ':val1': {
    'S': year +'-' + month + '-01'
  },
  ':val2': {
    'S': year + '-' + month + getDaysInMonth(month, year)
  }
}

':d': 'date' isn't necessary...

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Jonathan Irvin •

@kip13 thank you! I'm going to try that out now. Date is a restricted word in AWS. Restricted Words. Lame? Right?

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Jonathan Irvin •

Tried that and we're still not getting results. I'm storing dates as strings and "2018-01-01" as an example. Should I just start storing dates as timestamps?

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kip •

Isn't neccesary, you can use Strings

Can you try with FilterExpression ?

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kip •

If date isn't an index or sort key you need to use FilterExpression see

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kip •

@sublimegeek it works now ?

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Jonathan Irvin •

Not quite yet. I just made the source public, if you want to check it out.

jonathan-irvin / jelly-fin

A simple way to manage your finances with forecasting. We should automate our money, not make it automate us.

Jelly Fin

Finances are hard. It's one of the first adulting things everyone has to wrestle with. So, let's make it easy and automate it. Over the course of several years, my wife and I have tracked our finances using a forecasting method and had done it all within a spreadsheet. The time came where I wanted to take this concept and make it mobile using serverless architecture and clean design.

The idea is to take what we know: the transactions that are predictable like mortgage and insurance and just keep track of them against the account balance. Then take transactions that aren't predictable and try to predict them using seasonality analytics. Does your electric bill go up in the summer? Let's predict what it would be and try and account for it.

View on GitHub

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Jonathan Irvin •

Wait. I see what you mean.

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Jonathan Irvin • • Edited

@kip13 I think for my head I may use timestamps for the date. The math just works better that way.