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SQL update query using joins

...common table expression (since you're already on SQL 2005): with cte as ( select im.itemid ,im.sku as iSku ,gm.SKU as GSKU ,mm.ManufacturerId as ManuId ,mm.ManufacturerName ,im.mf_item_number ,mm.ManufacturerID , <your other field> from item_master im, gro...
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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2

...ata.frame(a = 1:3, b=letters[1:3]) require(sqldf) a1NotIna2 <- sqldf('SELECT * FROM a1 EXCEPT SELECT * FROM a2') And the rows which are in both data frames: a1Ina2 <- sqldf('SELECT * FROM a1 INTERSECT SELECT * FROM a2') The new version of dplyr has a function, anti_join, for exactly the...
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How do I simulate a hover with a touch in touch enabled browsers?

...for added usefulness, add this to your CSS as well: .hover { -webkit-user-select: none; -webkit-touch-callout: none; } To stop the browser asking you to copy/save/select the image or whatever. Easy! share ...
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How to reformat JSON in Notepad++?

..., "onclick" : "CloseDoc()" } ] } } } Tip: Select the code you want to reformat, then Plugins | JSTool | JSFormat. share | improve this answer | ...
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data.table vs dplyr: can one do something well the other can't or does poorly?

... ## data.table syntax left_join(DT2, DT1) ## dplyr syntax # 2. select columns while join DT1[DT2, .(z, i.mul)] left_join(select(DT2, x, y, mul), select(DT1, x, y, z)) # 3. aggregate while join DT1[DT2, .(sum(z) * i.mul), by = .EACHI] DF1 %>% group_by(x, y) %>% summarise(z = su...
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Hidden Features of MySQL

...that has an integer type, you can also refer to the column as "_rowid" in SELECT statements. In MySQL, the name of a PRIMARY KEY is PRIMARY Currently, only InnoDB (v5.1?) tables support foreign keys. Usually, you create all the indexes you need when you are creating tables. Any column declared...
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Android custom dropdown/popup menu

... android:paddingEnd="10dip"> <ImageView android:id="@+id/shoe_select_icon" android:layout_width="30dp" android:layout_height="30dp" android:layout_gravity="center_vertical" android:scaleType="fitXY" /> <TextView android:id="@+id/shoe_select_text" android:l...
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How do I specify different layouts for portrait and landscape orientations?

...mes depending on orientation and resolution, the device will automatically select the right one for its screen settings More info here: http://developer.android.com/guide/practices/screens_support.html under "Resource directory qualifiers for screen size and density" ...
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Increment value in mysql update query

...ion to numbers. To demonstrate, the following will produce the result 6: SELECT ' 05.05 '+'.95'; String concatenation in MySQL requires the CONCAT() function so there is no ambiguity here and MySQL converts the strings to floats and adds them together. I actually think the reason the initial q...
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How to show SQL queries run in the Rails console?

...ecord::Relation’s to_sql method: User.where(:id => 3).to_sql #=> "SELECT \"users\".* FROM \"users\" WHERE \"users\".\"id\" = 3" share | improve this answer | follo...