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What's the difference between an inverted index and a plain old index?
...inverted" even if it is just what everybody thinks of a "normal index". A SQL b-tree index stores for each word a pointer to all rows ("documents") containing it. There we call it "index". But in search engines we suddenly call this exact same procedure "inverted index". Not because it's fundamenta...
How to encrypt/decrypt data in php?
...ARY.
The output value, like the IV, is binary; to store those values in MySQL, consider using BINARY or VARBINARY columns. If this is not an option, you can also convert the binary data into a textual representation using base64_encode() or bin2hex(), doing so requires between 33% to 100% more stor...
Can dplyr package be used for conditional mutating?
...
case_when is now a pretty clean implementation of the SQL-style case when:
structure(list(a = c(1, 3, 4, 6, 3, 2, 5, 1), b = c(1, 3, 4,
2, 6, 7, 2, 6), c = c(6, 3, 6, 5, 3, 6, 5, 3), d = c(6, 2, 4,
5, 3, 7, 2, 6), e = c(1, 2, 4, 5, 6, 7, 6, 3), f = c(2, 3, 4,
2, 2, 7, 5, 2))...
best practice to generate random token for forgot password
...
I made a varchar(64) field in my sql database to store this token. I set $length to 64, but the string returned is 128 characters long. How can I get a string with a fixed size (here, 64 then) ?
– gordie
Feb 22 '16 at...
What is the recommended approach towards multi-tenant databases in MongoDB?
...fic to mongodb. My impression is that this is applicable for most of the NoSQL dbs I researched (CoachDB, Cassandra, CouchBase Server, etc.) due to the specifics of the database design.
Collections (or buckets or however they call it in different DBs) are not the same thing as security schemas in ...
What does “program to interfaces, not implementations” mean?
...AL.
2) Reuse
Following the example above, let's say we want to move from SQL Server (which our concrete DALClass uses) to MonogoDB. This would take major work, but NOT if we've programmed to an interface. In that case we just write the new DB class, and change (via the factory)
WorkerClass ->...
How to handle many-to-many relationships in a RESTful API?
...d}/players/{playerId}
In Restful-terms it helps a lot in not thinking of SQL and joins but more into collections, sub-collections and traversal.
Some examples:
# getting player 3 who is on team 1
# or simply checking whether player 3 is on that team (200 vs. 404)
GET /teams/1/players/3
# getti...
source of historical stock data [closed]
...ers and it will be able to store the data in a database of your choice: MS SQL, MySQL, SQLite, etc. It's open source, but I'll post more information on my blog when I get closer to releasing it (within a couple of days).
Another option is eclipse trader... it allows you to record the historical dat...
If REST applications are supposed to be stateless, how do you manage sessions?
...henticate? Because I guess storing a session, even if it is on a shared no-sql db among all servers, is not stateless, or is it?
– Carlos Navarro Astiasarán
May 13 '17 at 17:50
1
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What are the disadvantages of using persistent connection in PDO
... a solution to anything.
Further, most modern databases (including PostgreSQL) have their own preferred ways of performing connection pooling that don't have the immediate drawbacks that plain vanilla PHP-based persistent connections do.
To clarify a point, we use persistent connections at my wo...