How to use a variable as a case statement in Bash?
This makes use of grep to do the pattern matching for you, but still allows you to specify multiple pattern sets to be used in a case-statement structure. If either aaa, bbb, or ccc is the first argument to the script, this will output matched – pattern1.
How to use patterns in a case statement?
Pattern Matching Notation” only mentions ?, * and []. Thanks for contributing an answer to Stack Overflow! Please be sure to answer the question. Provide details and share your research!
Why do you need two variables in a case?
You need two variables for case because the or | pipe is parsed before the patterns are expanded. Shell patterns in variables are handled differently when quoted or unquoted as well: Explanation : the eval command makes the shell first expand the arguments so we are left with
How are shell patterns in variables handled differently?
Shell patterns in variables are handled differently when quoted or unquoted as well: Explanation : the eval command makes the shell first expand the arguments so we are left with and then it interprets again the command and executes it. awk is used to split string and test each part separately.
Is it possible to match multiple conditions in one case?
No, the basic structure for a case statement is that only one matching segment gets executed. Except for fall-through which you are rejecting. Also, it only works on some shells, not all, and has a syntax specific for each shell. The Bash syntax for fall-through is ;;&.
What’s the difference between a case statement in SQL?
The main difference, however, being that this only scans the input data set once, rather than once per condition (100 times in your case). I’ve also noticed that you may mean that the values returned by the CASE statements are fixed. All records that match the same condition get the exact sames values in value1 and value2.