var load_s = nlapiSearchRecord('transaction', null,

[

new nlobjSearchFilter('internalidnumber', 'item', 'equalto', 13412),

new nlobjSearchFilter('formuladate', null, 'onorafter', nlapiDateToString(new Date(new Date().setDate(new Date().getDate() - 30)))).setFormula('{trandate}')

],

[

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 30 = {trandate} THEN {quantity} ELSE 0 END').setLabel('30'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 29 = {trandate} THEN {quantity} ELSE 0 END').setLabel('29'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 28 = {trandate} THEN {quantity} ELSE 0 END').setLabel('28'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 27 = {trandate} THEN {quantity} ELSE 0 END').setLabel('27'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 26 = {trandate} THEN {quantity} ELSE 0 END').setLabel('26'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 25 = {trandate} THEN {quantity} ELSE 0 END').setLabel('25'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 24 = {trandate} THEN {quantity} ELSE 0 END').setLabel('24'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 23 = {trandate} THEN {quantity} ELSE 0 END').setLabel('23'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 22 = {trandate} THEN {quantity} ELSE 0 END').setLabel('22'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 21 = {trandate} THEN {quantity} ELSE 0 END').setLabel('21'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 20 = {trandate} THEN {quantity} ELSE 0 END').setLabel('20'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 19 = {trandate} THEN {quantity} ELSE 0 END').setLabel('19'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 18 = {trandate} THEN {quantity} ELSE 0 END').setLabel('18'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 17 = {trandate} THEN {quantity} ELSE 0 END').setLabel('17'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 16 = {trandate} THEN {quantity} ELSE 0 END').setLabel('16'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 15 = {trandate} THEN {quantity} ELSE 0 END').setLabel('15'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 14 = {trandate} THEN {quantity} ELSE 0 END').setLabel('14'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 13 = {trandate} THEN {quantity} ELSE 0 END').setLabel('13'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 12 = {trandate} THEN {quantity} ELSE 0 END').setLabel('12'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 11 = {trandate} THEN {quantity} ELSE 0 END').setLabel('11'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 10 = {trandate} THEN {quantity} ELSE 0 END').setLabel('10'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 09 = {trandate} THEN {quantity} ELSE 0 END').setLabel('09'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 08 = {trandate} THEN {quantity} ELSE 0 END').setLabel('08'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 07 = {trandate} THEN {quantity} ELSE 0 END').setLabel('07'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 06 = {trandate} THEN {quantity} ELSE 0 END').setLabel('06'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 05 = {trandate} THEN {quantity} ELSE 0 END').setLabel('05'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 04 = {trandate} THEN {quantity} ELSE 0 END').setLabel('04'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 03 = {trandate} THEN {quantity} ELSE 0 END').setLabel('03'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 02 = {trandate} THEN {quantity} ELSE 0 END').setLabel('02'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 01 = {trandate} THEN {quantity} ELSE 0 END').setLabel('01'),

new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula('CASE WHEN {today} - 00 = {trandate} THEN {quantity} ELSE 0 END').setLabel('00')

]

);

var filterArr = [];
for (var i = 30; i >= 0; i--){
    var formulaStr = 'CASE WHEN {today} - ' + i + ' = {trandate} THEN {quantity} ELSE 0 END';
    filterArr.push(
        new nlobjSearchColumn('formulanumeric', null, 'SUM').setFormula(formulaStr).setLabel(String(i))
    );
}

Adding this bit over a giant array is much cleaner

thats probably a reasonable formula if you want a column per day