How to build a query - Mailing list pgsql-novice

From JORGE MALDONADO
Subject How to build a query
Date
Msg-id CAAY=A7906Fp5kjnVHrLhdMg1EK3a+fxFR_0gcP3CPdM9jcRZ1g@mail.gmail.com
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Responses Re: How to build a query  (Mick <mickg01@verizon.net>)
Re: How to build a query  (Michael Wood <esiotrot@gmail.com>)
List pgsql-novice
I have to build a query at run-time which will contain a WHERE clause. There is a field in a table that has to be tested against several values but I do not know in advance how many values exist. For example,

SELECT fld1, fld2, fld3 FROM tblTable
WHERE fld1 = value[1] OR fld1 = value[2] OR fld1 = value[3]

value[] is an array that contains all of the possible values that fld1 may take but I do not know how many items such array has. A value of -1 in the array position indicates that it will not be taken into account. So, I need to traverse the whole array and include those values different from -1 in the WHERE clause. I can do a FOR...NEXT and concatenate the conditions getting only those values different than -1 but I wonder if this is a good approach; the query might grow depending on the number of valid values in the array. Please advice if there is a better way to build my query.

Respectfully,
Jorge Maldonado

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