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How to design a product table for many kinds of product where each product has many parameters

...urther If you would like to improve the performance of the queries you can select certain operations like for e.g. reporting or global text search and prepare for them index tables which would store required data and would be regenerated periodically, lets say every 30 minutes. You don't even need ...
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In Bash, how can I check if a string begins with some value?

... You can select just the part of the string you want to check: if [ "${HOST:0:4}" = user ] For your follow-up question, you could use an OR: if [[ "$HOST" == user1 || "$HOST" == node* ]] ...
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Are class names in CSS selectors case sensitive?

I keep reading everywhere that CSS is not case sensitive, but I have this selector 4 Answers ...
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Adding Permissions in AndroidManifest.xml in Android Studio?

...s you get a list of permissions and also hint to move caret up and down to select the same. share | improve this answer | follow | ...
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Is a Python list guaranteed to have its elements stay in the order they are inserted in?

...represent lists of things so much as they describe the extent of a certain selection of things. The internal structure of set, how its elements are stored relative to each other, is usually not meant to convey useful information. In some implementations, sets are always internally sorted; in others ...
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Multiple INSERT statements vs. single INSERT with multiple VALUES

...t One place where this information is leveraged is shown by @Lieven here SELECT * FROM (VALUES ('Lieven1', 1), ('Lieven2', 2), ('Lieven3', 3))Test (name, ID) ORDER BY name, 1/ (ID - ID) Because at compile time it can determine that the Name column has no duplicates it...
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Django - filtering on foreign key properties

... Is this going to hit the DB twice, should I be using select_related() to make this more optimal? – Fraser Graham Dec 30 '09 at 22:52 5 ...
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OS detecting makefile

...detected_OS := $(patsubst MINGW%,MSYS,$(detected_OS)) endif Then you can select the relevant stuff depending on detected_OS: ifeq ($(detected_OS),Windows) CFLAGS += -D WIN32 endif ifeq ($(detected_OS),Darwin) # Mac OS X CFLAGS += -D OSX endif ifeq ($(detected_OS),Linux) CFLAGS ...
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what is the most efficient way of counting occurrences in pandas?

...].astype('str').stack().value_counts().sum() which equates to setting each selected column to str type, stacking all individual columns on top, forming basically one column and then doing the value_counts() and sum() on that one column. :) Stack is pretty useful, it might not be the most obvious cho...
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How to limit setAccessible to only “legitimate” uses?

...his via source-code analysis tools; e.g. custom pmd or findbugs rules. Or selective code review of code identified by (say) grep setAccessible .... In response to the followup None of my classes have any semblance of enforceable privacy what-so-ever. The singleton pattern (putting doubts abou...