ruby on rails - next available record id -

- 

  @user = user.new   
  @ उपयोगकर्ता आईडी  शून्य पर लौटता है लेकिन मुझे बचाने से पहले इसे जानना आवश्यक है I क्या यह संभव है?   
 
 
 नहीं, आप सहेजने से पहले आईडी नहीं पा सकते हैं। आईडी नंबर डेटाबेस से आता है लेकिन जब तक आप  save  को कॉल नहीं करते, तब तक डेटाबेस आईडी को निर्दिष्ट नहीं करेगा यह सब मानते हुए है कि आप निश्चित रूप से ActiveRecord का उपयोग कर रहे हैं।

Comments

Post a Comment

Popular posts from this blog

qt - switch/case statement in C++ with a QString type -

-
I want to use switch-case in my program but the compiler generates an error. How can I use the switch statement with QString ? The compiler gives me this error: The expression of the switch type 'QString' is invalid My code is as follows : boolStopWord (the word QString) {bool flag = false; Switch (word) {case "the": flag = true; break ; "On" case: flag = true; break ; Case "in": flag = true; break ; Case "your": flag = true; break ; Case "near": flag = true; break ; Case "all": flag = true; break ; Case "this": flag = true; break ; } Return flag; } How do I use the switch statement with a Caststring ? You can not use the switch statement in C ++ language with integral or enum types. You can formally enter the square type of object in the switch statement, but this means that the compiler will look for a user-defined conversion to convert it to an integral or enum type.
Read more

python - sqlite3.OperationalError: near "REFERENCES": syntax error - foreign key creating -

-
I'm trying to create a predefined key after checking the manual and I wrote it: Db.execute ("create table" Table 2 (id, integer primary key, somedata integer) "db.execute" (table creation table 2 does not exist (name text, maintain reference (id) ") and found this: sqlite 3. Operation error: near" references ": syntax error Your second ligne is wrong db.execute ("create table if table does not exist 2 (name text, my_id integer, foreign key (my_id) reference Maintenance (ID)) ") as explained
Read more

Python's equivalent for Ruby's define_method? -

-
What is a Python equivalent for Ruby's define_method , which is the dynamic generation of class methods will allow? (As can be seen in Wikipedia) Functions are first-class objects in Python and assign them The properties of a class or an example can be a way of doing the same thing as a Wikipedia example: colors = {"black": "000", "red": "F00", "green": "0f0", "yellow": "ff0", "blue": "00f", "magenta": "fff", "cyan": "0ff", "white": " FFF "} Class MyStream (ARR): Pass for Name, Code in colors.iteritems (): def _in_colour ( W code = code): return '& lt; Span style = "color:% s" & gt;% s & lt; / Span & gt; ' % (Code, self) setter (histrive, "in_" + name, _in_ color)
Read more