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How to add column if not exists on PostgreSQL?
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DO $$ BEGIN BEGIN CREATE INDEX type_idx ON table1 USING btree (type); EXCEPTION WHEN duplicate_table THEN RAISE NOTICE 'Index exists.'; END; END;$$; the same approach in CREATE INDEX ;) Thanks for Your answer,
– marioosh
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What's the difference between TRUNCATE and DELETE in SQL
...a large amount of undo. Truncate generates a negligible amount of each.
Indexes
Oracle
A truncate operation renders unusable indexes usable again. Delete does not.
Foreign Keys
A truncate cannot be applied when an enabled foreign key references the table. Treatment with delete depends on th...
What's the best way to get the last element of an array without deleting it?
...Undefined offset: -1 in Command line code on line 1
N4 = Notice: Undefined index: in Command line code on line 1
Based on this output I draw the following conclusions:
newer versions of PHP perform better with the exception of these options that became significantly slower:
option .6. $x = en...
JavaScript variables declare outside or inside loop?
...rs in the body of the loop should be declared before the loop begins. The index value of the loop is clearly a special case (and is hoisted) and doesn't not help the OP at all.
– mkoistinen
Sep 10 '10 at 14:13
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git replace local version with remote version
...s of one file (or a selection) from upstream. You don't want to affect the index directly (so you would go through add + commit as usual).
Simply do
git checkout remote/branch -- a/file b/another/file
If you want to do this for extensive subtrees and instead wish to affect the index directly use...
Git: can't undo local changes (error: path … is unmerged)
... Not specifying HEAD will make git checkout check out from the index, which is a weaker operation (the content source is the index rather than HEAD). Furthermore I don’t think that makes a difference in this case at all - with the specific problem the question stated. Did you try that?...
What do column flags mean in MySQL Workbench?
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@Ivan -- it is a way to help index values while preventing duplicates. For example -- e-mail and SSN fields for a unique list of customers should be a unique index, since you frequently do lookups using those fields and they shouldn't repeat. For arbitra...
How do I update the element at a certain position in an ArrayList? [duplicate]
I have one ArrayList of 10 String s. How do I update the index 5 with another String value?
5 Answers
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Where can I find the solutions to “The Algorithm Design Manual”? [closed]
... it seems the wiki was moved to: nbl.cewit.stonybrook.edu:60128/mediawiki/index.php/…
– alampada
Apr 30 '13 at 17:45
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Test a string for a substring [duplicate]
...There are several other ways, besides using the in operator (easiest):
index()
>>> try:
... "xxxxABCDyyyy".index("test")
... except ValueError:
... print "not found"
... else:
... print "found"
...
not found
find()
>>> if "xxxxABCDyyyy".find("ABCD") != -1:
... ...