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How can I define a composite primary key in SQL?
...
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...
Replace tabs with spaces in vim
... what if i want to save it with spaces ? right now when I :wq and open the file again i am back to tabs
– Gorkem Yurtseven
Apr 2 '14 at 0:50
1
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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 ...
String contains - ignore case [duplicate]
...You can use
org.apache.commons.lang3.StringUtils.containsIgnoreCase(CharSequence str,
CharSequence searchStr);
Checks if CharSequence contains a search CharSequence irrespective of
case, handling null. Case-insensitivity is defined as by
String.equalsIg...
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...
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...
Index (zero based) must be greater than or equal to zero
...
String.Format must start with zero index "{0}" like this:
Aboutme.Text = String.Format("{0}", reader.GetString(0));
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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...
Declare and initialize a Dictionary in Typescript
... which exact TS version). I
get these errors in VS, as you would expect: Index signatures are
incompatible. Type '{ firstName: string; }' is not assignable to type
'IPerson'. Property 'lastName' is missing in type '{ firstName:
string; }'.
Apparently this doesn't work when passing the ini...
Why doesn't list have safe “get” method like dictionary?
...f:
def safe_list_get (l, idx, default):
try:
return l[idx]
except IndexError:
return default
You could even monkeypatch it onto the __builtins__.list constructor in __main__, but that would be a less pervasive change since most code doesn't use it. If you just wanted to use this with...