Questions from prescriptions table, drug, ndc in MIMIC-IV

Prerequisites

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  • Checked the online documentation: https://mimic.mit.edu/
  • Checked that your issue isn't already addressed: https://github.com/MIT-LCP/mimic-code/issues?utf8=%E2%9C%93&q=

Description

Description of the issue, including:

• what you have tried
• references to similar issues
• queries demonstrating your question (if applicable)

Hello. I'm glad to use this dataset for studying, so I'm thankful to people who related to this one.
However, I'm trying to understand 'prescriptions.csv' table in MIMIC-IV, but I got some questions.

Here's some questions.

1. about OxycoDONE drug name, for example, there're some information included the drug name in several hadm_id in prescriptions table.
   Like these,

I can see the fact that the number on the right is the counted one each drug name included oxycodone. (I did .lower())
So, each drug name is all different???

2. From the number 1 question above, if there is the same thing, and if there is something different, how could I get to know it??
   The printed lines are (drug, gsn, ndc).

Above the image, I have no idea what's the difference from that. Like,
(1), (2) -> difference (OK)
(1), (3) -> how can I get it's different with the NDC code??

(1) OxycoDONE |004224 | 66591091332.0
(2) OxycoDONE |004225 | 406055262.0
(3) OxycoDONE |004224 | 66689040150.0

4. I checked the issue #980, as follow.

The respondent said that it corresponds ndc code with this link, https://www.accessdata.fda.gov/scripts/cder/ndc/index.cfm

Then, I can't match the NDC code between MIMIC-IV and NDC database from FDA.
I couldn't even find the code 66591091332.0 in FDA database, even though I searched it like these.
6659-1091-332,66591-0913-32, etc

So, how can I get to understand the ndc code in prescriptions table, and are those code really corresponding with the database??
And how can I convert drug name to NDC from the database?

I hope anyone gives me some references.

Thank you.

Start with the MIMIC-IV prescriptions.csv table and the drug, gsn, and ndc fields described in the issue, then review issue #980 and the linked FDA NDC reference. Done means providing a clear, documented explanation of the identifiers, their relationships, and how the reported NDC values should be interpreted.