insert values only if they do not already exist in table

[kabbi~thkek]

Hello I want to insert some values from one table (A) into another table (b).
However there are some values in table A which exist two times in table A. I
only want to insert values one time. So If a certain field value also exist in
some other row (same fieldname) then I don't want to insert it twice. It
doesn't matter which of the two rows will be inserted.

Can this be done with MySQL? Maybe with some Control Flow Functions?

Hopefully someone can help me.

Thank you in advance.

Gr, Kabbi

[Dan Bracuk]

use the keyword distinct in your select clause.

[kabbi~thkek]

Hi Dan Bracuk,

Thank you for your answer! I already have another question about this. I also
do not want to insert values from A into B if they already exist in B.

I believe this should also be possible, do you perhaps know how?

Grt, Kabbi

[kabbi~thkek]

Hi,

I used DISTINCT, however I now only get the values for that specific row I
used the distinct for (without any duplicates!!). However I want to get all
data(all columns) from a row but only the rows for where there is no duplicate
item in column G

SELECT *
FROM inventimport WHERE DISTINCT G

Will not work I guess?

[BKBK]

I want to get all data(all columns) from a row but only the rows for where
there is no duplicate item in column G
A quick idea to get you started:



<cfquery name="myQuery1" datasource="myDSN">
SELECT G, count(*) as G_frequency
FROM inventimport
GROUP BY G
</cfquery>

<cfquery name="myQuery2" dbtype="Query">
SELECT G
FROM myQuery1
WHERE G_frequency < 2
</cfquery>

<cfquery name="myQuery3" datasource="#application.dsn#">
SELECT *
FROM inventimport
WHERE G in (#QuotedValueList(myQuery2.G)#)
</cfquery>

[Dan Bracuk]

Originally posted by: kabbi~thkek
Hi,

I used DISTINCT, however I now only get the values for that specific row I
used the distinct for (without any duplicates!!). However I want to get all
data(all columns) from a row but only the rows for where there is no duplicate
item in column G

SELECT *
FROM inventimport WHERE DISTINCT G

Will not work I guess?



I said your select clause, not your where clause.

[kabbi~thkek]

:) yes, thank you!!