Re: [Tarantool-patches] [PATCH v2 1/3] sql: allow conversion of numeric binary values to DOUBLE

[Nikita Pettik <korablev@tarantool.org>]

On 30 Dec 16:01, imeevma@tarantool.org wrote:
> This patch allows to convert binary values consisting of numeric
> literals to numbers.

What is the justification for this change? I see no reason to allow
implicitly casting blobs to floating points.

> Follow-uo #3812

-> up

> ---
>  src/box/sql/vdbemem.c                |  2 +-
>  test/sql-tap/numcast.test.lua        | 25 ++++++++++++++++++++++++-
>  test/sql-tap/tkt-80e031a00f.test.lua |  8 ++++----
>  test/sql/types.result                |  7 +++++--
>  4 files changed, 34 insertions(+), 8 deletions(-)
> 
> diff --git a/src/box/sql/vdbemem.c b/src/box/sql/vdbemem.c
> index df3f0d8..3c5e5fc 100644
> --- a/src/box/sql/vdbemem.c
> +++ b/src/box/sql/vdbemem.c
> @@ -516,7 +516,7 @@ sqlVdbeRealValue(Mem * pMem, double *v)
>  	} else if ((pMem->flags & MEM_UInt) != 0) {
>  		*v = (double)pMem->u.u;
>  		return 0;
> -	} else if (pMem->flags & MEM_Str) {
> +	} else if ((pMem->flags & (MEM_Blob | MEM_Str)) != 0) {
>  		if (sqlAtoF(pMem->z, v, pMem->n))
>  			return 0;
>  	}
> diff --git a/test/sql-tap/numcast.test.lua b/test/sql-tap/numcast.test.lua
> index 07117d0..a45daef 100755
> --- a/test/sql-tap/numcast.test.lua
> +++ b/test/sql-tap/numcast.test.lua
> @@ -1,6 +1,6 @@
>  #!/usr/bin/env tarantool
>  test = require("sqltester")
> -test:plan(20)
> +test:plan(22)
>  
>  --!./tcltestrunner.lua
>  -- 2013 March 20
> @@ -147,4 +147,27 @@ test:do_catchsql_test(
>          1,"Tuple field 1 type does not match one required by operation: expected integer"
>      })
>  
> +--
> +-- Allow to convert binary values consisting of numeric literals
> +-- to numbers.
> +--
> +test:do_execsql_test(
> +    "cast-3.1",
> +    [[
> +        CREATE TABLE td (i DOUBLE PRIMARY KEY);
> +        INSERT INTO td VALUES(X'3132332E35');
> +        INSERT INTO td VALUES(X'31323334');
> +        SELECT * FROM td;
> +    ]], {
> +        123.5, 1234
> +    })
> +
> +test:do_execsql_test(
> +    "cast-3.2",
> +    [[
> +        SELECT CAST(X'39' AS DOUBLE), CAST(X'39' AS DOUBLE) / 10;
> +    ]], {
> +        9, 0.9
> +    })
> +
>  test:finish_test()
> diff --git a/test/sql-tap/tkt-80e031a00f.test.lua b/test/sql-tap/tkt-80e031a00f.test.lua
> index a0e6539..01f4265 100755
> --- a/test/sql-tap/tkt-80e031a00f.test.lua
> +++ b/test/sql-tap/tkt-80e031a00f.test.lua
> @@ -380,23 +380,23 @@ test:do_execsql_test(
>          -- </tkt-80e031a00f.30>
>      })
>  
> -test:do_catchsql_test(
> +test:do_execsql_test(
>      "tkt-80e031a00f.31",
>      [[
>          SELECT x'303132' IN t1
>      ]], {
>          -- <tkt-80e031a00f.31>
> -        1, 'Type mismatch: can not convert varbinary to integer'
> +        false
>          -- </tkt-80e031a00f.31>
>      })
>  
> -test:do_catchsql_test(
> +test:do_execsql_test(
>      "tkt-80e031a00f.32",
>      [[
>          SELECT x'303132' NOT IN t1
>      ]], {
>          -- <tkt-80e031a00f.32>
> -        1, 'Type mismatch: can not convert varbinary to integer'
> +        true
>          -- </tkt-80e031a00f.32>
>      })
>  
> diff --git a/test/sql/types.result b/test/sql/types.result
> index 6d0aefd..8c0186d 100644
> --- a/test/sql/types.result
> +++ b/test/sql/types.result
> @@ -1760,8 +1760,11 @@ box.execute("SELECT CAST(x'' AS DOUBLE);")
>  ...
>  box.execute("SELECT CAST(x'35' AS DOUBLE);")
>  ---
> -- null
> -- 'Type mismatch: can not convert varbinary to double'
> +- metadata:
> +  - name: CAST(x'35' AS DOUBLE)
> +    type: double
> +  rows:
> +  - [5]
>  ...
>  box.execute("SELECT CAST(CAST(x'35' AS STRING) AS DOUBLE);")
>  ---
> -- 
> 2.7.4
>