Converting fields from VarChar to String

[Christer Olsson]

26 jan 2012 kl. 19.40 skrev Ruslan Zasukhin:

> On 1/26/12 3:16 PM, "Christer Olsson" <christer at ljusaideer.se> wrote:
> 
> Hi Christer,
> 
>> We're considering to change several VarChar fields to String fields to avoid
>> some corruption troubles we are seeing with VarChar fields.
> 
>> Is it considered 
>> safe to just convert the fields or should we make new String fields, copy the
>> values from VarChar fields and then drop VarChar fields?
> 
> Best,
> Christer
> 
> 
> 
> A) it should be safe if strings will not be truncated.
> 
> B) so question is what length of VarChar declared?
>    what strings really there?
> 
> C) string with big N can take much more disk and be slower.
> String field okay on my view for 5-20 chars only strings.

Our biggest fields are 128 chars.

> =======
> May be there is sense wait few days yet to see 5.0 betas
> And make tests with it.
> 
> We have add journaling with automatic rollback on open.
> This  feature should eliminate any corruptions from crashes of app

That would be great. I've spent the last four hours restoring a db from backup after a crash. The db was impossible to open in VStudio.

Best,
Christer

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