chapter49.amp

%%[
    /* Declare variables */
    var @rows, @dataExtensionName, @attributeToSearch, @valueToSearch, @rowCount, @index, @row
    var @column1, @column2

    /* Set the name of the data extension to be used */
    set @dataExtensionName = "My_DataExtension"

    /* Set the attribute to search by in the data extension */
    set @attributeToSearch = {{attributeToSearch}}

    /* Set the value to search for in the given attribute */
    set @valueToSearch = {{valueToSearch}}

    /* Use the LookupRows function to fetch all rows that match the search criteria */
    set @rows = LookupRows(@dataExtensionName, @attributeToSearch, @valueToSearch)

    /* Get the total number of rows returned by the LookupRows function */
    set @rowCount = RowCount(@rows)

    /* Check if any rows were returned */
    if @rowCount > 0 then
        /* Loop through each row and extract values for specified columns */
        for @index = 1 to @rowCount do
            set @row = Row(@rows, @index)

            {{columnAssignments}}  

            /* Optionally: you can output these values for debugging or further use */
            OutputLine(concat({{outputLineColumns}}))
        next @index
    else
        RaiseError("No record found, skipping this send.", true)
    endif
]%%