大约有 6,000 项符合查询结果（耗时：0.0176秒） [XML]
Why do we need Abstract factory design pattern?
...a sources. Assume your application supports different data stores. (e.g. a SQL Database and an XML file). You have two different data access interfaces e.g. an IReadableStoreand IWritableStore defining the common methods expected by your application regardless of the type of data source used.
Which...
Java: Date from unix timestamp
...er compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.
Where to obtain the java.time classes?
Java SE 8, Java SE 9, and later
Built-in.
Part of the standard Java API with a bundled implementation.
Java 9 adds some minor features and fixes.
Java SE 6 and Jav...
The maximum recursion 100 has been exhausted before statement completion
...
Not the answer you're looking for? Browse other questions tagged sql stored-procedures common-table-expression or ask your own question.
List of Rails Model Types
...
The attributes are SQL types, hence the following are supported:
:binary
:boolean
:date
:datetime
:decimal
:float
:integer
:primary_key
:string
:text
:time
:timestamp
These are documented under column in the Active Record API.
...
in a “using” block is a SqlConnection closed on return or exception?
...even for the new maintenance programmer who will support it later:
using (SqlConnection connection = new SqlConnection(connectionString))
{
int employeeID = findEmployeeID();
try
{
connection.Open();
SqlCommand command = new SqlCommand("UpdateEmployeeTable",...
What is wrong with using goto? [duplicate]
...gramming, as I've just discovered when trying to make a loop continue in T-SQL.
– Denziloe
Feb 19 '19 at 16:35
...
Using union and order by clause in mysql
I want to use order by with union in mysql query.
I am fetching different types of record based on different criteria from a table based on distance for a search on my site.
The first select query returns data related to the exact place search .
The 2nd select query returns data related to distance ...
Should a RESTful 'PUT' operation return something
...
If the backend of the REST API is a SQL relational database, then
you should have RowVersion in every record that can be updated (to avoid the lost update problem)
you should always return a new copy of the record after PUT (to get the new RowVersion).
If ...
Simple way to calculate median with MySQL
...e simplest (and hopefully not too slow) way to calculate the median with MySQL? I've used AVG(x) for finding the mean, but I'm having a hard time finding a simple way of calculating the median. For now, I'm returning all the rows to PHP, doing a sort, and then picking the middle row, but surely th...
Truncate all tables in a MySQL database in one command?
...
Drop (i.e. remove tables)
mysql -Nse 'show tables' DATABASE_NAME | while read table; do mysql -e "drop table $table" DATABASE_NAME; done
Truncate (i.e. empty tables)
mysql -Nse 'show tables' DATABASE_NAME | while read table; do mysql -e "truncate tab...