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How to count instances of character in SQL Column
...LESCE(NULLIF(LEN(@StringToFind), 0), 1) --protect division from zero
FROM [Table To Search]
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Repeater, ListView, DataList, DataGrid, GridView … Which to choose?
...t you trying to achieve
Gridview - Limited in design, works like an html table. More in built functionality like edit/update, page, sort. Lots of overhead.
DataGrid - Old version of the Gridview. A gridview is a super datagrid.
Datalist - more customisable version of the Gridview. Also has some o...
Boolean Field in Oracle
Yesterday I wanted to add a boolean field to an Oracle table. However, there isn't actually a boolean data type in Oracle. Does anyone here know the best way to simulate a boolean? Googling the subject discovered several approaches
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Difference between FOR and AFTER triggers?
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There is no difference, they do the same thing.
CREATE TRIGGER trgTable on dbo.Table FOR INSERT,UPDATE,DELETE
Is the same as
CREATE TRIGGER trgTable on dbo.Table AFTER INSERT,UPDATE,DELETE
An INSTEAD OF trigger is different, and fires before and instead of the insert and can be used on...
How to see full query from SHOW PROCESSLIST
...ck on the "Full texts" option ("← T →" on top left corner of a results table) to see untruncated results.
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Filter data.frame rows by a logical condition
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we can use data.table library
library(data.table)
expr <- data.table(expr)
expr[cell_type == "hesc"]
expr[cell_type %in% c("hesc","fibroblast")]
or filter using %like% operator for pattern matching
expr[cell_type %like% "hesc...
JPA: what is the proper pattern for iterating over large result sets?
Let's say I have a table with millions of rows. Using JPA, what's the proper way to iterate over a query against that table, such that I don't have all an in-memory List with millions of objects?
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Common MySQL fields and their appropriate data types
...e specific - and storage is not the only cost. Sorting data and temporary tables (memory engine) will use the fixed amount.
– Morgan Tocker
Sep 17 '10 at 15:34
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Unpivot with column name
I have a table StudentMarks with columns Name, Maths, Science, English .
Data is like
4 Answers
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