SQL

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Hi,

we're planning some work on our SQL Query Plan functionality for a future release of InterSystems IRIS and are interested to hear how you're using them today, or what'd keep you from using them. Rather than try and fit everything in a rigid survey, I thought a simple thread on our beloved DC might also reveal some use patterns that we support or could do a better job on. 

Last reply 4 February 2020
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Hi All,

We have few queries which are simple selects . For simplicity let's say there is a query that joins two tables and gets few columns and both tables have no indexes.

Select Tab1.Field1, Tab2.Field2
From Table1 Tab1
Join Table2 Tab2
On Tab2.FK = Tab1.PK

When we do query plan for this it shows approx 6 million,  however if we make a simple adjustment to the query

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Hi Community!

There are two general ways to execute arbitrary SQL  in serverside ObjectScript code: EmbeddedSQL and ObjectScript SQL a.k.a. Dynamic SQL.

E.g. if we want to get the value of the property of instance with a certain ID using SQL we can do:

&sql(SELECT Name INTO :name FROM Sample.Person WHERE ID=1)

write name

Same result with %SQL.Statement:

set rs=##class(%SQL.Statement).%ExecDirect(,"SELECT Name as name FROM Sample.Person where ID=1")
  do rs.%Next()
  write rs.name

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