MonetDB table statistics -


below portion of statistics of 1 of tables. i'm not sure how understand width column. values in bytes? if so, know fname , lname have higher ascii char counts 5 , 6 , there 1 char long values in mname.

update 1. below output of select * statistics. i'm showing first 5 columns of ouput.

+--------+---------+------------------------+---------+-------+ | schema | table   | column                 | type    | width | +========+=========+========================+=========+=======+ | abc    | targets | fname                  | varchar |     5 | | abc    | targets | mname                  | varchar |     0 | | abc    | targets | lname                  | varchar |     6 |

the column width shows "byte-width of atom array" (defined in gdk.h). not entire story in case of string columns, because here atom array stores offsets string heap.

monetdb uses variable-width columns, because if there few distinct string values, 64-bit offsets waste of memory. in case, fname column needs string offsets 5 bytes, or 40 bits, , lname needs 6 bytes (48 bits). change if new values inserted.

the 0 value mname interesting, because width initialised 1 new columns. version using?


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