Power Query: Function to search a column for a list of keywords and return only rows with at least one match - excel

Question

I am making a simple Google-like search function in Power Query.
Let's say I have a column called Description in a table called Database. The user then inputs some search queries like "dog, cat, animals". I want to filter Database for rows that contain at least one of these keywords. They keywords can change each time, depending on what the user types in a named range in Excel.
I know you can filter a column in Power Query for multiple keywords, like this:
FilterRows = Table.SelectRows(LastStep, each Text.Contains([English], "dog") or Text.Contains([English], "cat")),
but those keywords are static, and the column is also static. I want to be able to control both the keywords and the column name as variables. I think I need to write a function but I am not sure how to start.

Answer 1

Your question requires several moving parts.
First, I would get the keywords from a named range "Keywords" into a table like this:
{KeywordTbl}
let
GetKeywords = if Excel.CurrentWorkbook(){[Name="Keywords"]}[Content]{0}[Column1] = null then null else Text.Split(Excel.CurrentWorkbook(){[Name="Keywords"]}[Content]{0}[Column1], ", "),
ConvertToTable = Table.FromList(GetKeywords,null,{"Keywords"})
in
ConvertToTable
Secondly, store the column name where you want to search in an Excel named range called "ColName". Then pull the named range into Power Query like this:
{ColName}
let
GetColName = Excel.CurrentWorkbook(){[Name="ColName"]}[Content]{0}[Column1]
in
GetColName
Then I would write a function that takes 4 variables, the table and column you want to look in, and the table and column containing the keywords:
{SearchColForKeywords}
(LookInTbl as table, KeywordTbl as table, LookInCol as text, KeywordCol as text) =>
let
RelativeMerge = Table.AddColumn(LookInTbl, "RelativeJoin",
(Earlier) => Table.SelectRows(KeywordTbl,
each Text.Contains(Record.Field(Earlier, LookInCol), Record.Field(_, KeywordCol), Comparer.OrdinalIgnoreCase))),
ExpandRelativeJoin = Table.ExpandTableColumn(RelativeMerge, "RelativeJoin", {KeywordCol}, {"Keywords found"}),
FilterRows = Table.SelectRows(ExpandRelativeJoin, each [Keywords found] <> null and [Keywords found] <> ""),
// Concatenate multiple keyword founds line into one line
GroupAllData = Table.Group(FilterRows, {"Word ID"}, {{"AllData", each _, type table [First column=text, Second column=text, ... your other columns=text]}}),
AddCol = Table.AddColumn(GroupAllData, "Keywords found", each [AllData][Keywords found]),
ExtractValues = Table.TransformColumns(AddCol, {"Keywords found", each Text.Combine(List.Transform(_, Text.From), ", "), type text}),
DeleteAllData = Table.RemoveColumns(ExtractValues,{"AllData"}),
MergeQueries = Table.NestedJoin(DeleteAllData, {"Word ID"}, FilterRows, {"Word ID"}, "DeleteAllData", JoinKind.LeftOuter),
ExpandCols = Table.ExpandTableColumn(MergeQueries, "DeleteAllData", {"First Col name", "Second col name", ... "Your Other column names here"}),
DeleteKeywordsFound = Table.RemoveColumns(ExpandCols,{"Keywords found"})
in
DeleteKeywordsFound
FYI, half of this function has been developed by a user named lmkeF on PowerBI community. The full discussion is here. I merely improved on his solution.
Finally, I will use that function in another query like this:
StepName = SearchColForKeywords(MainTbl, KeywordTbl, ColName, "Keywords"),
You may customize the 4 variable names.