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Tag: sqldf

Select Rows That Does Not Contain any Negative Or Missing Value

Assume a database table has a few hundred columns. In SQL statements, how would you select rows/records that do not contain any negative or missing value? Can you do it using the sqldf package for R users? Here is an example of data frame with 6 rows and 2 columns: The SQL statement(s) should only return a ta…

get first row fo each group SQL

I have data like below. I would like to get the top choice for each gender from the following data I have tried mapping the choices by descending order as below : BUT, I would like to get the following table where i get the top choice for eachgender : Answer If you are runing MySQL 8.0, you can use

Count based on multiple conditions using sqldf

Hi all I’m writing a sql query on R using sqldf and seem to hit a roadblock. I have a table with an Id column, two dates columns and a grouping by column. The query I’m writing is From this query the result I’m getting is Whichis correct based on the query. What I want to achieve is if my

Preserving times Class with sqldf

I am using sqldf to join several tables, but I am having trouble preserving the times class set with the chron package on a column. I used the method=”name__class” argument to the sqldf function and …