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Use of *args and **kwargs [duplicate]
...le named arguments that you have not defined in advance:
>>> def table_things(**kwargs):
... for name, value in kwargs.items():
... print( '{0} = {1}'.format(name, value))
...
>>> table_things(apple = 'fruit', cabbage = 'vegetable')
cabbage = vegetable
apple = fruit
...
rake db:schema:load vs. migrations
...n (very similar to your schema.rb file) and updating the schema_migrations table to reflect this change. Be very careful when doing this! You can easily delete your production data if you aren't careful.
As a side note, I strongly believe that you should never put data creation in the migration fil...
Are foreign keys really necessary in a database design?
... code using things like ON DELETE CASCADE. This means that if you have one table containing users and another containing orders or something, then deleting a user could automatically delete all orders that point to that user.
...
What is the use of the @Temporal annotation in Hibernate?
...on and you want to store precise date/time or both (TIMESTAMP) in database table.
The temporal precision is not specified in core Java APIs. @Temporal is a JPA annotation that converts back and forth between timestamp and java.util.Date. It also converts time-stamp into time. For example, in the s...
Laravel Eloquent ORM Transactions
...ging this.
After reading THIS stackoverflow answer, I realized my database tables were using MyISAM instead of InnoDB.
For transactions to work on Laravel (or anywhere else as it seems), it is required that your tables are set to use InnoDB
Why?
Quoting MySQL Transactions and Atomic Operations docs ...
java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...tes you need to update characher-set and collation for utf8mb4:
database table/column:
alter table <some_table> convert to character set utf8mb4 collate utf8mb4_unicode_ci
database server connection (see)
On my development enviromnt for #2 I prefer to set parameters on command line when st...
Using an ORM or plain SQL? [closed]
...ased on Java beans get/set methods. This is a TON of boilerplate for every table, for every column and ... here's the real anti-pattern: Just to expose every field as if it were public. In effect, having a get/set method on fields in an object/table/row is very close to violating every tenant of inf...
PHP & mySQL: Year 2038 Bug: What is it? How to solve it?
...b hardly a legacy platform yet.
Here is a process for altering a database table column to convert TIMESTAMP to DATETIME. It starts with creating a temporary column:
# rename the old TIMESTAMP field
ALTER TABLE `myTable` CHANGE `myTimestamp` `temp_myTimestamp` int(11) NOT NULL;
# create a new DAT...
In the shell, what does “ 2>&1 ” mean?
...ing both streams to the same destination.
Here is how the file descriptor table looks like after Bash has redirected both streams:
As you can see, both stdout and stderr now point to file. So anything written to stdout and stderr gets written to file.
There are several ways to redirect both str...
How to update only one field using Entity Framework?
Here's the table
16 Answers
16
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