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LouisGac wrote: ok, could you please attach the survey so we can do some testing here?
LouisGac wrote: indeed: you should update to 2.73
Note: 'Survey size' refers to the maximum number of questions (and answers) in your survey - don't confuse this with the number of replies on your survey (there is no limitation on that). Theoretically there would also be no limit on the maximum number of questions/answers in LimeSurvey. But the database engine you are using has several limits. The most important one is the limit on the number of fields(columns) in the result table.
MySQL ISAM: The sum of the lengths of the VARCHAR and CHAR columns in a table may be up to 64KB.
MySQL InnoDB: Maximum number of 1000 columns
MS SQL Server 2000: Maximum number of 1024 columns
Postgres: Maximum number of 250-1600 columns depending on column types. The maximum number of columns can be quadrupled by increasing the default block size to 32k.
Take care here: please think about what you do before you do it: an array of 10 x 10 items already costs you 100 columns. Rule of thumb: every item on the screen that can be filled in or selected costs one column!
The mySQL ISAM engine is the most tricky one (see mysql documentation for more information). As it allows only up to 65,535 bytes per row and utf8 characters can require up to three bytes per character the maximum may be only 21,844 characters (but this depends on your DB encoding).
You can roughly calculate the size of your survey like this:
Every multiple numerical question: 20 chars for each answer
Every multiple choice & array question answers: 5 chars for each answer
Every other question type: 5 chars
Add 10% for the usual overhead
There should be some kind of system calculator in LimeSurvey
Limitations, as far as I understand, come from MySql itself.
In "Toad for mysql" I tried manually creating a table based on the script of the created table and adding fields of the same type and dimension (varchar (5)) to the number where I encountered the problem. Experimentally (reducing the number of fields) reached the 1575 field, when the table allows creating.
After, I tried varchar (5) instead of varchar (1). The result is the same. 1575 fields - the number at which I was able to create the table.
So Limesurvey has nothing to do with it.