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Extracting specific columns from a data frame

...r package, if your data.frame is called df1: library(dplyr) df1 %>% select(A, B, E) This can also be written without the %>% pipe as: select(df1, A, B, E) share | improve this answer ...
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Can you use an alias in the WHERE clause in mysql?

...ts an unknown column. Is there any way to get around this issue? I need to select records that have a rating higher than x. Rating is calculated as the following alias: ...
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How do I get the “id” after INSERT into MySQL database with Python?

... Does not works with duplicated records using insert, select and where. – e-info128 Oct 27 '18 at 19:20 add a comment  |  ...
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Add support library to Android Studio project

...oject Structure (Press F4 on PC and Command+; on MAC) on your project). 2.Select Modules on the left pane. 3.Choose your project and you will see Dependencies TAB above the third Column. 4.Click on the plus sign in the bottom. Then a tree-based directory chooser dialog will pop up, navigate to yo...
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SQL - Rounding off to 2 decimal places

... Could you not cast your result as numeric(x,2)? Where x <= 38 select round(630/60.0,2), cast(round(630/60.0,2) as numeric(36,2)) Returns 10.500000 10.50 share | improve ...
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SQL WHERE.. IN clause multiple columns

...a derived table from the subquery, and join table1 to this derived table: select * from table1 LEFT JOIN ( Select CM_PLAN_ID, Individual_ID From CRM_VCM_CURRENT_LEAD_STATUS Where Lead_Key = :_Lead_Key ) table2 ON table1.CM_PLAN_ID=table2.CM_PLAN_ID AND table1.Individual=table2.Indi...
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Ways to save enums in database

...ering the cards by the numerical value of the enumeration is meaningless: SELECT Suit FROM Cards ORDER BY SuitID; --where SuitID is integer value(4,1,3,2,0) Suit ------ Spade Heart Diamond Club Unknown That's not the order we want - we want them in enumeration order: SELECT Suit FROM Cards ORDE...
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How to create P12 certificate for iOS distribution

...hain Access where it will be matched up with the private key. You can then select the cert, and open the arrow to also select the private key and export them together as a .p12 file from Keychain Access. share | ...
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How to select the last record of a table in SQL?

This is a sample code to select all records from a table. Can someone show me how to select the last record of that table? ...
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Drop data frame columns by name

...op=FALSE to keep R from converting your data frame to a vector if you only select a single column. Don't forget that data frames are lists, so list selection (one-dimensional like I did) works perfectly well and always returns a list. Or a data frame in this case, which is why I prefer to use it. ...