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How can I define a composite primary key in SQL?
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SELECT * FROM voting WHERE QuestionID = 7
it will use the primary key's index. If however you do this:
SELECT * FROM voting WHERE MemberID = 7
it won't because to use a composite index requires using all the keys from the "left". If an index is on fields (A,B,C) and your criteria is on B and C...
From inside of a Docker container, how do I connect to the localhost of the machine?
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Perfect if you want to use php xdebug on Windows 10 : ``` zend_extension = xdebug.so xdebug.default_enable = 0 xdebug.remote_enable = 1 xdebug.remote_connect_back = 0 xdebug.remote_host = host.docker.internal```
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postgresql list and order tables by size
...al_relation_size(<relation_name>) - gets total size of table and its index in bytes.
pg_relation_size(<relation_name>) - gets relation (table/index) size in bytes.
pg_index_size(<relation_name>) - gets index size of the relation in bytes.
current_database() - gets the currently ...
Asking the user for input until they give a valid response
...True:
try:
# Note: Python 2.x users should use raw_input, the equivalent of 3.x's input
age = int(input("Please enter your age: "))
except ValueError:
print("Sorry, I didn't understand that.")
#better try again... Return to the start of the loop
contin...
How do I check to see if a value is an integer in MySQL?
...ay to check to see if a value is an integer? Something like is_int() in PHP is what I am looking for.
11 Answers
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Get all directories within directory nodejs
...s.readdir rootDir, (err, files) ->
dirs = []
for file, index in files
if file[0] != '.'
filePath = "#{rootDir}/#{file}"
fs.stat filePath, (err, stat) ->
if stat.isDirectory()
dirs.push(file...
Index (zero based) must be greater than or equal to zero
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String.Format must start with zero index "{0}" like this:
Aboutme.Text = String.Format("{0}", reader.GetString(0));
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What are the performance characteristics of sqlite with very large database files? [closed]
... complicates queries, but for me, it's a worthwhile tradeoff to be able to index this much data. An additional advantage is that I can just delete a whole db file to drop a day's worth of data (a common operation for my application).
I'd probably have to monitor table size per file as well to see w...
elasticsearch v.s. MongoDB for filtering application [closed]
...s of a record, can be updated several times a day and this can call for re-indexing of that record to elastic. For that reason alone, using elastic as the sole data store is not a good option for us, as we can't update select fields; we would need to re-index a document in its' entirety. This is not...
Why can't I save CSS changes in Firebug? [closed]
... on demand to your web server (by communication with a one-file webservice php script).
Documentation can be found at my homepage or on the addon page
I would appreciate any testing, bug reports, comments, ratings, discussion on this, as it's still in early beta, but should already work fine.
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