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Database Design for Revisions?
...operly does not cost much in terms of a performance hit. You could use an xml schema and even indexes to get over possible performance problems. Your comment about parsing the xml is valid but you could easily create a view using xquery - which you can include in queries and join to. Something li...
Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
...s inline help:
\h ALTER TABLE
Also documented in the postgres docs (an excellent resource, plus easy to read, too).
ALTER TABLE tablename ADD CONSTRAINT constraintname UNIQUE (columns);
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What exactly is Apache Camel?
I don't understand what exactly Camel does.
23 Answers
23
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How can I merge two commits into one if I already started rebase?
...this error as there is nothing for the first commit to squash into.
The Fix
First get back to where you started with
$ git rebase --abort
Say your history is
$ git log --pretty=oneline
a931ac7c808e2471b22b5bd20f0cad046b1c5d0d c
b76d157d507e819d7511132bdb5a80dd421d854f b
df239176e1a2ffac927d8b4...
Google Maps Android API v2 Authorization failure
...e.name) at APIs console and get API KEY
to copy directory ANDROID_SDK_DIR/extras/google/google_play_services/libproject/google-play-services_lib to root of your project
to add next line to the YOUR_PROJECT/project.properties
android.library.reference.1=google-play-services_lib
to add next lines ...
HTML input - name vs. id [duplicate]
...iframe>, <img>, <map>, <input>, <select>, <textarea>
Name does not have to be unique, and can be used to group elements together such as radio buttons & checkboxes
Can not be referenced in URL, although as JavaScript and PHP can see the URL there are workarounds
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How to get rspec-2 to give the full trace associated with a test failure?
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Yes! this is exactly what I needed. stack trace to the actual error not the spec stack.
– DiegoSalazar
Jan 31 '13 at 17:16
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When to use CouchDB over MongoDB and vice versa
...link,
MongoDB: If you need dynamic queries. If you prefer to define indexes, not map/reduce functions. If you need good performance on a big DB. If you wanted CouchDB, but your data changes too much, filling up disks.
CouchDB : For accumulating, occasionally changing data, on which pre-defined qu...
Windows batch files: .bat vs .cmd?
...th NT. But I continue to see .bat files everywhere, and they seem to work exactly the same using either suffix. Assuming that my code will never need to run on anything older than NT, does it really matter which way I name my batch files, or is there some gotcha awaiting me by using the wrong suff...
MySQL: Large VARCHAR vs. TEXT?
... and message types (all integer types) I need to save the actual message text as either VARCHAR or TEXT. I'm setting a front-end limit of 3000 characters which means the messages would never be inserted into the db as longer than this.
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