Re: Joins with WebObjects
Re: Joins with WebObjects
- Subject: Re: Joins with WebObjects
- From: Guido Neitzer <email@hidden>
- Date: Sat, 19 Mar 2005 17:01:11 +0100
"Geoff Hopson" <email@hidden> wrote:
> The queries look the same to me, but obviously they are producing
> different performance results.
Sorry, I should have made that more clear. Second query has an explicit
join:
DGA_DIENSTLEISTER d join DGA_DIENSTLEISTER_ZU_FACHRICHTUNG z
on d.id = z.id2,
The first doesn't have this. I think the Frontbase plugin doesn't create
good SQL for the join.
> I'm no Frontbase expert, but do they have anything like the 'explain
> plan' stuff in Oracle? It might be worth analysing the two queries and
> the effectiveness of any indexes you have on your tables.
Yes they have, but I don't know how to read them. I'm not database expert,
perhaps you can read something from it (I attach the two informations at the
end of this mesage).
> With help from that, I have managed to improve performance of several
> webobjects applications by either changing the order of the indexed
> columns in an index, or the order of the qualifiers in the EOQualifier,
> or a combination of the two.
I have played around with that, but wasn't successful. Perhaps the Frontbase
guys can tell something on monday.
> Or you could always give the 'rawRowsForSQL' a spin on EOUtilities...
Argl ... I wanted to avoid that for now ... ;-)
But if I have to ... :-(
cug
FAST:
{
GROUPS = (
(
{
"ROW_COUNT" = 6;
"SCHEMA_NAME" = webobjects;
"TABLE_NAME" = "DGA_DIENSTLEISTER";
}
),
(
{
"ROW_COUNT" = 33383;
"SCHEMA_NAME" = webobjects;
"TABLE_NAME" = "DGA_DIENSTLEISTER_ZU_FACHRICHTUNG";
}
),
(
{
"ROW_COUNT" = 1;
"SCHEMA_NAME" = webobjects;
"TABLE_NAME" = "DGA_DIENSTLEISTER_FACHRICHTUNG";
}
)
);
"SVI_JOINS" = (
{
ESTIMATE = 1;
"INDEX_NAME" = "_I0000000104";
"JOIN_COLUMNS" = (ID2);
"ROW_COUNT" = 33383;
"SCHEMA_NAME" = webobjects;
"TABLE_NAME" = "DGA_DIENSTLEISTER_ZU_FACHRICHTUNG";
}
);
"SVI_LITERALS" = (
{
ESTIMATE = 6;
"INDEX_NAME" = "plz_index";
"ROW_COUNT" = 7;
"SCHEMA_NAME" = webobjects;
"SELECT_INFO" = ("PLZ LIKE '45257'");
"TABLE_NAME" = "DGA_DIENSTLEISTER";
TIME = "0.000238";
},
{
ESTIMATE = 1;
"INDEX_NAME" = "_I0000000102";
"ROW_COUNT" = 1;
"SCHEMA_NAME" = webobjects;
"SELECT_INFO" = ("NAME LIKE 'Physiotherapeuten'");
"TABLE_NAME" = "DGA_DIENSTLEISTER_FACHRICHTUNG";
TIME = "0.000019";
}
);
}
==================================================
And slow:
{
GROUPS = (
(
{
"ROW_COUNT" = 1;
"SCHEMA_NAME" = webobjects;
"TABLE_NAME" = "DGA_DIENSTLEISTER_FACHRICHTUNG";
}
),
(
{
"ROW_COUNT" = 33383;
"SCHEMA_NAME" = webobjects;
"TABLE_NAME" = "DGA_DIENSTLEISTER_ZU_FACHRICHTUNG";
}
),
(
{
"ROW_COUNT" = 6;
"SCHEMA_NAME" = webobjects;
"TABLE_NAME" = "DGA_DIENSTLEISTER";
}
)
);
"SVI_JOINS" = (
{
ESTIMATE = 1;
"INDEX_NAME" = "_I0000000014";
"JOIN_COLUMNS" = (ID);
"ROW_COUNT" = 6;
"SCHEMA_NAME" = webobjects;
"TABLE_NAME" = "DGA_DIENSTLEISTER";
}
);
"SVI_LITERALS" = (
{
ESTIMATE = 6;
"INDEX_NAME" = "plz_index";
"ROW_COUNT" = 7;
"SCHEMA_NAME" = webobjects;
"SELECT_INFO" = ("PLZ LIKE '45257'");
"TABLE_NAME" = "DGA_DIENSTLEISTER";
TIME = "0.000171";
},
{
ESTIMATE = 1;
"INDEX_NAME" = "_I0000000102";
"ROW_COUNT" = 1;
"SCHEMA_NAME" = webobjects;
"SELECT_INFO" = ("NAME LIKE 'Physiotherapeuten'");
"TABLE_NAME" = "DGA_DIENSTLEISTER_FACHRICHTUNG";
TIME = "0.000019";
}
);
}
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