Different number of rows from SQL query to solution

When I run the solution the query in the StackExchange Data Explorer
for the following project it returns 7147 rows whereas in the solution, according to the .info of the dataframe based on the .csv from the query, it returned 8839 rows.

Is this due to changes on StackExchange Data Science data explorer or is there potentially something that I am doing wrong? I am inclined to believe the former as I copied the query from solution and got the 7147 rows (therefore this occurs before I read the .csv into a df).

My Code: Transact SQL on StackExchange Data Science Data Explorer

SELECT Id, PostTypeID, CreationDate, Score, Viewcount, Tags, AnswerCount, FavoriteCount 
FROM Posts
WHERE YEAR(CreationDate) = 2019 AND PostTypeID = 1

My Code (Jupyter Notebook):

import pandas as pd
questions = pd.read_csv("questions2019.csv", parse_dates = ["CreationDate"])
questions.info()

What I expected to happen:

<class 'pandas.core.frame.DataFrame'>
RangeIndex: 8839 entries, 0 to 8838
Data columns (total 7 columns):
 #   Column         Non-Null Count  Dtype         
---  ------         --------------  -----         
 0   Id             8839 non-null   int64         
 1   CreationDate   8839 non-null   datetime64[ns]
 2   Score          8839 non-null   int64         
 3   ViewCount      8839 non-null   int64         
 4   Tags           8839 non-null   object        
 5   AnswerCount    8839 non-null   int64         
 6   FavoriteCount  1407 non-null   float64       
dtypes: datetime64[ns](1), float64(1), int64(4), object(1)
memory usage: 483.5+ KB

What actually happened:

<class 'pandas.core.frame.DataFrame'>
RangeIndex: 7147 entries, 0 to 7146
Data columns (total 8 columns):
 #   Column         Non-Null Count  Dtype         
---  ------         --------------  -----         
 0   Id             7147 non-null   int64         
 1   PostTypeID     7147 non-null   int64         
 2   CreationDate   7147 non-null   datetime64[ns]
 3   Score          7147 non-null   int64         
 4   Viewcount      7147 non-null   int64         
 5   Tags           7147 non-null   object        
 6   AnswerCount    7147 non-null   int64         
 7   FavoriteCount  1546 non-null   float64       
dtypes: datetime64[ns](1), float64(1), int64(5), object(1)
memory usage: 446.8+ KB

I know it doesn’t really affect how I approach the rest of the project but obviously is annoying that I cannot check my results against the solution.

srauten Srauten, I think the database may be updated now, administrator might have removed unnecessary entries from the table.

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