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When should I use a NoSQL database instead of a relational database? Is it okay to use both on the s
What are the advantages of using NoSQL databases? I've read a lot about them lately, but I'm still unsure why I would want to implement one, and under what circumstances I would want to use one.
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TSQL Pivot without aggregate function
... This should be the accepted answer as it shows the proper use of the TSQL Pivot command.
– Ubercoder
Jan 2 '19 at 15:05
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What is the difference between Left, Right, Outer and Inner Joins?
...imple Example: Lets say you have a Students table, and a Lockers table. In SQL, the first table you specify in a join, Students, is the LEFT table, and the second one, Lockers, is the RIGHT table.
Each student can be assigned to a locker, so there is a LockerNumber column in the Student table. More...
What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
...s the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
6 Answers
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Can I have multiple primary keys in a single table?
...xed columns on the same table). Be sure to consult your specific flavor of SQL's manual for details on the exact language syntax used.
– 4AM
Jan 25 '18 at 17:16
add a comment
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How to get last N records with activerecord?
... Try this with Postgres! I've certainly had trouble with first. In SQL the order isn't guaranteed unless you specify it, but MySQL is more forgiving.
– Ghoti
Jul 15 '12 at 10:56
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Storing money in a decimal column - what precision and scale?
...age. Accountants generally seem to favour four decimal places.
PS Avoid SQL Server's MONEY data type because it has serious issues with accuracy when rounding, among other considerations such as portability etc. See Aaron Bertrand's blog.
Microsoft and language designers chose banker's roundin...
A connection was successfully established with the server, but then an error occurred during the pre
...while some threads threw this exception, some other threw:
System.Data.SqlClient.SqlException (0x80131904): Connection Timeout Expired. The timeout period elapsed while attempting to consume the pre-login handshake acknowledgement. This could be because the pre-login handshake failed or the se...
How to speed up insertion performance in PostgreSQL
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See populate a database in the PostgreSQL manual, depesz's excellent-as-usual article on the topic, and this SO question.
(Note that this answer is about bulk-loading data into an existing DB or to create a new one. If you're interested DB restore performance wi...
Disabling contextual LOB creation as createClob() method threw error
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Basically here we are simply checking
whether we can call the
java.sql.Connection methods for LOB
creation added in JDBC 4. We not only
check whether the java.sql.Connection
declares these methods, but also
whether the actual java.sql.Connection
instance implements them (i.e. can b...