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问题 I will say when I first got carrierwave up and running, everything was working totally fine aside from the size scaling of the avatar. So now after I tried to do scaling, everything went to hell. I uninstalled the gem, did a migration to remove avatar from user, then did another migration to add. Still the same error. Note I am doing rails g uploader Avatar, NOT image. I have not touched the avatar_uploader.rb file, aside from adding require 'carrierwave/orm/activerecord' on the top line. So,

问题 I have written a code in PHP , to see the JSON string output. But i am getting null value. <?php $l=array(); $l[] = array('a'=>'@cÐaÐjÔÐ J kf _ÞÒi^ ','b'=>']éÞ[ѯРQtÍ]hà_ , `ËSÐ J heZ Òhi'); echo $j = json_encode($l); ?> Output-: [{"a":null,"b":null}] Why the JSON output is coming in null. I am expecting that there must be character encoding problem. i want the output in following format. [{"a":"@cÐaÐjÔÐ J kf _ÞÒi^","b":"]éÞ[ѯРQtÍ]hà_ , `ËSÐ J heZ Òhi"}] Please help me out. Please suggest

问题 I have written a code in PHP , to see the JSON string output. But i am getting null value. <?php $l=array(); $l[] = array('a'=>'@cÐaÐjÔÐ J kf _ÞÒi^ ','b'=>']éÞ[ѯРQtÍ]hà_ , `ËSÐ J heZ Òhi'); echo $j = json_encode($l); ?> Output-: [{"a":null,"b":null}] Why the JSON output is coming in null. I am expecting that there must be character encoding problem. i want the output in following format. [{"a":"@cÐaÐjÔÐ J kf _ÞÒi^","b":"]éÞ[ѯРQtÍ]hà_ , `ËSÐ J heZ Òhi"}] Please help me out. Please suggest

问题 I have written a code in PHP , to see the JSON string output. But i am getting null value. <?php $l=array(); $l[] = array('a'=>'@cÐaÐjÔÐ J kf _ÞÒi^ ','b'=>']éÞ[ѯРQtÍ]hà_ , `ËSÐ J heZ Òhi'); echo $j = json_encode($l); ?> Output-: [{"a":null,"b":null}] Why the JSON output is coming in null. I am expecting that there must be character encoding problem. i want the output in following format. [{"a":"@cÐaÐjÔÐ J kf _ÞÒi^","b":"]éÞ[ѯРQtÍ]hà_ , `ËSÐ J heZ Òhi"}] Please help me out. Please suggest

问题 Conception In the Org_Structure there are unique combinations of departments and offices. In the Emp_Positions table each employee is assigned to the certain combination of department/office or "Chain" in the organizational structure. But some employees should not belong to offices, so they are assigned to a chain where office_id column is NULL. On the second image such employee is colored in red. The Bug The provided stored procedure can find only employees of those chains where both dep_id

问题 I am creating a INSERT script and I am coming across a problem. There is a middle initial field that is a char(1) Sometimes the records don't have anything in that field so I put a NULL. This causes a Data too long for column error. I don't want to just put ' ' as that leaves just a blanks space. Is there another way around this? 回答1: It sounds like you may be attempting to insert the string 'NULL' into the char(1) field, rather than an SQL NULL, and you have strict SQL mode enabled, which

问题 This is a follow up question from here. I have some output and was able to add a total column but now I need to use the column to add percentage like this: | LESSONID RESPONSE COUNT-> | 0 | 1 | 2 | 3 | 4 | N | --------------------------------------------------------------------------------------- |lesson1 | 1 (20%) | 1 (20%) | 1 (20%) | 1 (20%) | 1 (20%) | 5 | |lesson2 | 1 (20%) | 1 (20%) | 1 (20%) | 2 (40%) | 0 | 5 | |lesson3 | 1 (20%) | 1 (20%) | 0 | 3 (60%) | 0 | 5 | |lesson4 | 0 | 1 (20%)

问题 This is a follow up question from here. I have some output and was able to add a total column but now I need to use the column to add percentage like this: | LESSONID RESPONSE COUNT-> | 0 | 1 | 2 | 3 | 4 | N | --------------------------------------------------------------------------------------- |lesson1 | 1 (20%) | 1 (20%) | 1 (20%) | 1 (20%) | 1 (20%) | 5 | |lesson2 | 1 (20%) | 1 (20%) | 1 (20%) | 2 (40%) | 0 | 5 | |lesson3 | 1 (20%) | 1 (20%) | 0 | 3 (60%) | 0 | 5 | |lesson4 | 0 | 1 (20%)

问题 I have created a Zapier Zap to populate data from a SmartSheet to a MySQL database. I have it branching so if the row does not already exist in MySQL a new row is created. This part works fine. In my second branch, if the row already exists then the data in the row is updated with new data from the SmartSheet row. When existing data is replaced with new data the Zap works fine. E.g. for an example existing MySQL row: +--------+---------------+--------------------+ | row_id | email_comment |

问题 This question already has answers here : Method Overloading for null argument (7 answers) Closed 3 years ago . I am confused with the Output of the following two programs. When I'm only having two methods with parameters as String and Object in Program 1 it gives me output as String . But when I add a new method with parameter as Integer in Program 2 it won't compile and gives error as The method nullTest(Object) is ambiguous for the type testNull Program 1 : package onkartest; public class