NullColumn

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Not supported in Just BASIC Not supported in Liberty BASIC Not supported in Liberty BASIC 5 Supported in Run BASIC

Description

When using a QueryResultRow object Run BASIC will translate NULL values into 0 when asked for a numeric value, and into an empty string when asked for a string.
You can change the default values to something else if you like by changing the contents of the NullColumn$ and NullColumn variables, which are globally visible.

Syntax

These variables are case sensitive.

  1. NullColumn
  2. NullColumn$

Hints

NullColumn and NullColumn$ are only supported by SQL database objects

Example

' set null value for display
NullColumn = -9999
NullColumn$ = "Nothing"

' check DBs existence
files #accessor, "Records.db"
exists = #accessor hasAnswer()
if exists then kill "Records.db"

' create DB
sqliteconnect #records, "Records.db"
query$ = "create table Payables (company char(50), invoice char(12), due integer, amt char(10))"
#records execute(query$)

' fill DB
data "IBM","1029A",38945,"19.95"
data "Brooks Brothers","029528",38915,"199.95"
data "Joe's Garage","330Z",38995,"48.99"
data "Toyota","834-18",38999,"129.95"

for i = 1 to 4
    read company$, invoice$, due, amt$
    query$ = "insert into Payables (company, invoice, due, amt) values ('"; company$; "', '"; invoice$; "', "; due; ", '"; amt$; "')"
    if i = 2 then query$ = "insert into Payables default values"
    #records execute(query$)
next

query$ = "select * from Payables"
#records execute(query$)
print "Render query result as a table"
render #records

print
print "Render query result manually"
dim items$(3, 3)
i = 0
while #records hasanswer()
    #row = #records #nextrow()

    items$(0, i) = #row company$()
    items$(1, i) = #row invoice$()
    items$(2, i) = str$(#row due())
    items$(3, i) = #row amt$()

    i = i + 1
wend
table #manual, items$()
#manual columnnames("company,invoice,due,amt")
render #manual

#records disconnect()
end

Useful Procedures

' Place a useful function or sub using this keyword here