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SET versus SELECT when assigning variables?
...es between the SET and SELECT statements when assigning variables in T-SQL?
4 Answers
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What is the difference between related SQLite data-types like INT, INTEGER, SMALLINT and TINYINT?
When creating a table in SQLite3, I get confused when confronted with all the possible datatypes which imply similar contents, so could anyone tell me the difference between the following data-types?
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How can you program if you're blind?
...platform and visual studio as my environment. I also use tools like the MS Sql enterprise studio and others for DB access, network monitoring etc.
I tried to spend some time with emacspeak but since my work was mostly based on the MS platform, never really spent a lot of time there.
I have also spen...
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
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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...