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From Taewoo Kim <wangs...@gmail.com>
Subject Re: Counting character positions inside a string
Date Tue, 30 Jan 2018 20:03:16 GMT
+1

Best,
Taewoo

On Tue, Jan 30, 2018 at 11:57 AM, Murtadha Hubail <hubailmor@gmail.com>
wrote:

> +1
>
> Cheers,
> Murtadha
>
> On 01/30/2018, 10:55 PM, "Mike Carey" <dtabass@gmail.com> wrote:
>
>     +1
>
>     Likewise
>
>
>     On 1/30/18 11:22 AM, Till Westmann wrote:
>     > Sounds good to me.
>     >
>     > +1
>     >
>     > Cheers,
>     > Till
>     >
>     > On 29 Jan 2018, at 18:54, Dmitry Lychagin wrote:
>     >
>     >> All,
>     >>
>     >> We would like to change how string functions count character
>     >> positions inside a string.
>     >> Currently string functions position(), substring() and some others
>     >> assume that the first character is at position 1.
>     >> The proposal is to change the first position to 0, to better align
>     >> with array element positions (which also start with 0), and other
>     >> languages (JavaScript, etc).
>     >> This change will also apply to binary functions (see below) and will
>     >> be effective in both SQLPP and AQL.
>     >>
>     >> The following functions will be affected:
>     >> position(),
>     >> regexp_position(),
>     >> substring()/substr(),
>     >> sub_binary(),
>     >> find_binary()
>     >>
>     >> This might be a disrupting change for some users so we will also
>     >> introduce a cluster-wide configuration parameter
>     >> (“compiler.stringoffset”) for backwards compatibility:
>     >> compiler.stringoffset = 0   // first character position is assumed
> to
>     >> be 0 (new default)
>     >> compiler.stringoffset = 1   // first character position is assumed
> to
>     >> be 1 (backwards-compatible setting)
>     >>
>     >> The query migration path is straightforward, for example:
>     >> substring(“abcdef”, 1) will need to be changed to
> substring(“abcdef”,
>     >> 0), etc, same applies to sub_binary().
>     >> position(), regexp_position(), and find_binary() will return one
> less
>     >> than they used to, but would still return -1 if the value is not
> found.
>     >>
>     >> Please share your comments and concerns.
>     >> Thanks,
>     >> -- Dmitry
>
>
>
>
>

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