Store data from an array for later comparison

will be helpful for those in need I haven't used SQLAlchemy much, but I'd guess it uses Python's operator overloading to handle those comparisons. If that's true, then you can use the properties' magic methods. For example:

Product.manufacturer == 'bar' => Product.manufacturer.__eq__('bar')
Product.manufacturer != 'foo' => Product.manufacturer.__ne__('foo')

method_map = {'==': '__eq__', '!=': '__ne__'}
comparison = getattr(Product.manufacturer, method_map[op])   # Here, 'op' is the operator (!=)
sqlalchemy.or_(comparison('foo'), comparison('bar'))         # Equivalent to: Product.manufacturer != 'foo' || Product.manufacturer != 'bar'

around this issue Experience tells me that option 1 should be faster, because you're making just one call to the compare method and storing the result for reuse. Facts that support this belief are that local variables live on the stack and making a method call involves a lot more work from the stack than just pushing a value onto it. However profiling is the best and safest way to compare two implementations.
The first thing to realise is that the java compiler and JVM together may optimise your code how it wishes to get the job done most efficiently (as long as certain rules are followed). Chances are there is no difference in performance, and chances are also that what is actually executed is not what you think it is. One really important difference however is in debugging: if you put a break point on the return statement for the store-in-variable version, you can see what was returned from the call, otherwise you can't see that in a debugger. Even more handy is when you seemingly uselessly store the value to be returned from the method in a variable, then return it, so you may see what's going to be returned from a method while debugging, otherwise there's no way to see it.

seems to work fine Since you're using o.toString() to get the String value of all returned rows, you could create an object to hold each column's value, e.g.:

class CellValue
{
    int cellTye;
    String cellValue;

    CellValue(int cellType,String cellValue) 
    {
        this.cellType=cellType;
        this.cellValue=cellValue;
    }
}

ArrayList<ArrayList<CellValue>> cells = new ArrayList<>();

ResultSetMetaData rsmd = resTablesData1.getMetaData();
int colCount = rsmd.getColumnCount();

while(resTablesData1.next()) {
    ArrayList<CellValue> row = new ArrayList<>();
    for (int k=0; k<colCount ; k++) {
        String colName = rsmd.getColumnName(i);
        Object o = resTablesData1.getObject(colName);
        row.add(new CellValue(rsmd.getColumnType(),o.toString());
    }
    cells.add(row);
}

With these it helps I have a binary tree program. And Im trying to get this output from the program: , try this

void outToArray(node *tree, int **arr){
//Write elements of tree to the array.
    if(tree){
        outToArray(tree->left, arr);
        *(*arr)++ = tree->data;
        outToArray(tree->right, arr);
    }
}

int cmp(const void *a, const void *b){
    int x = *(int *)a;
    int y = *(int *)b;
    return x < y ? -1 : x > y;
}

int main(void) {
    node *root = NULL;
    int i, j;
    int arr[] = {55, 31, 49, 64, 65, 39, 47, 98, 97, 1};
    int n = sizeof(arr)/sizeof(*arr);
    int arrExp[sizeof(arr)/sizeof(*arr)] = {0};
    int *ap = arrExp;

    for (i = 0; i < n; i++)
        insert(&root, arr[i]);

    print_preorder(root);
    puts("\n");

    outToArray(root, &ap);
    qsort(arr, n, sizeof(*arr), cmp);

    for (i = 0; i < n; i++) {
        if (arr[i] != arrExp[i]) {
            puts("not same");
            return -1;
        }
    }
    puts("same");

    return 0;
}

void outToArray(node *tree, int **arr){
//pre-order output 
    if(tree){
        *(*arr)++ = tree->data;
        outToArray(tree->left, arr);
        outToArray(tree->right, arr);
    }
}

int main(void) {
    node *root = NULL;
    int i, j;
    int arr[] = {55, 31, 49, 64, 65, 39, 47, 98, 97, 1};
    int n = sizeof(arr)/sizeof(*arr);
    int arrExp[] = {55, 31, 49, 64, 65, 39, 47, 98, 97, 1};
    int *ap = arr;

    for (i = 0; i < n; i++)
        insert(&root, arr[i]);

    print_preorder(root);
    puts("\n");

    outToArray(root, &ap);

    for (i = 0; i < n; i++) {
        if (arr[i] != arrExp[i]) {
            puts("not same");
            return -1;
        }
    }
    puts("same");

    return 0;
}

　　　　55
　　　／　＼
　　31　　　64
　／　＼　　　＼
１　　　49　　　65
　　　／　　　　　＼
　　39　　　　　　　98
　　　＼　　　　　／
　　　　47　　　97