大约有 1,948 项符合查询结果(耗时:0.0282秒) [XML]

https://stackoverflow.com/ques... 

How to do an INNER JOIN on multiple columns

...ave an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'INNER_JOIN airports to_port ON (to_port.code = flights.tairport) WHERE ' at line 7 – Kiril Mar 2 '10 at 21:26 ...
https://stackoverflow.com/ques... 

What is PostgreSQL explain telling me exactly?

MySQL's explain output is pretty straightforward. PostgreSQL's is a little more complicated. I haven't been able to find a good resource that explains it either. ...
https://stackoverflow.com/ques... 

Creating a config file in PHP

...ction to escape data for embedding into PHP code as exists for HTML, URLs, MySQL statements, shell commands.... Serialized data This is relatively efficient for small amounts of configuration (up to around 200 items) and allows for use of any PHP data structure. It requires very little code to crea...
https://stackoverflow.com/ques... 

When should I use a NoSQL database instead of a relational database? Is it okay to use both on the s

...roblems where a RDBMS is not a viable solution, for all other things I use MySQL (or SQLite for testing). If you need a NoSQL db you usually know about it, possible reasons are: client wants 99.999% availability on a high traffic site. your data makes no sense in SQL, you find yourself doing mult...
https://stackoverflow.com/ques... 

How does the SQL injection from the “Bobby Tables” XKCD comic work?

...ample, you can only run multiple statements in one SQL string by using the mysqli_multi_query function. You can, however, manipulate an existing SQL statement via SQL injection without having to add a second statement. Let's say you have a login system which checks a username and a password with th...
https://stackoverflow.com/ques... 

What are the advantages of using a schema-free database like MongoDB compared to a relational databa

I'm used to using relational databases like MySQL or PostgreSQL, and combined with MVC frameworks such as Symfony, RoR or Django, and I think it works great. ...
https://stackoverflow.com/ques... 

Count(*) vs Count(1) - SQL Server

...not the case for Oracle or most other modern RDBMS but is the case for old MySQL's storage engine, MyISAM), then COUNT(*) would just need to take the value from the metadata. – Quassnoi Oct 31 '18 at 18:29 ...
https://stackoverflow.com/ques... 

Storing money in a decimal column - what precision and scale?

... For Mysql, I recommend storing the integer (2500) as a bigint if you intend on sorting by the amount. And don't waste your time with PHP 32bit when dealing with big integers, upgrade to 64bit or Node.JS ;) –...
https://stackoverflow.com/ques... 

MIN/MAX vs ORDER BY and LIMIT

...OM `tbl`; Simply because it is ANSI compatible. Limit 1 is particular to MySql as TOP is to SQL Server. share | improve this answer | follow | ...
https://stackoverflow.com/ques... 

Multiple columns index when using the declarative ORM extension of sqlalchemy

...f you have a dictionary for table_args like I currently do? table_args = {'mysql_engine':'InnoDB'} – Nick Holden Sep 1 '11 at 8:39 ...