Re: Difference between DESC & user_tab_columns

Praveen wrote:

>
> ------------------------------------------------------------------------
>
> Subject:
> Difference between DESC & user_tab_columns
> From:
> Praveen <nospam_at_nospam.com>
> Date:
> Fri, 22 Oct 2004 12:46:40 -0700
>
>
> Hi..All,
>
> When I do a DESC on a table , one of the columns shows the
> datatype(lenght) as Number(38). But when I look at the details of the
> column it shows something else. How does it come up with a different
> lenght Or where does desc pick it from when you do a DESC? Is there any
> other logic involved?
>
> Column Details :
>
>
> TABLE_NAME COLUMN_NAME
> ------------------------------ ------------------------------
> DATA_TYPE DAT
> ----------------------------------------------------------------------------------------------------------
> ---
> DATA_TYPE_OWNER DATA_LENGTH DATA_PRECISION DATA_SCALE N
> COLUMN_ID DEFAULT_LENGTH
> ------------------------------ ----------- -------------- ---------- -
> ---------- --------------
> DATA_DEFAULT NUM_DISTINCT
> --------------------------------------------------------------------------------
> ------------
> LOW_VALUE
> ----------------------------------------------------------------
> HIGH_VALUE DENSITY NUM_NULLS NUM_BUCKETS LAST_ANAL SAMPLE_SIZE
> ----------------------------------------------------------------
> ---------- ---------- ----------- --------- -----------
> CHARACTER_SET_NAME CHAR_COL_DECL_LENGTH GLO USE AVG_COL_LEN
> -------------------------------------------- -------------------- ---
> --- -----------
> TEST_TABLE TEST_COLUMN
> NUMBER
> 22 0 N 4
> 3
> C102
> C106 .333333333 0 1 26-MAR-04 143
> NO NO 2
>
>
>
>
>
>
> TIA
>
> P/
>

NUMBER(38) where 38 refers to the number of Decimal Digits

compared to a data length of 22BYTES
Why are they different? is that your question?

The numbers seem about right to me. If I did my arithmetic right, 22bytes should hold 50-60 decimal digits. basically they are measuring different units.

Obviously not all the needed info. is available in the USER_TAB_COLUMNS view.

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