nimrodshn

    /// insert a key value pair possibly splitting nodes along the way.
    pub fn insert(&mut self, kv: KeyValuePair) -> Result<(), Error> {
        let root_offset = self.wal.get_root()?;
        let root_page = self.pager.get_page(&root_offset)?;
        let new_root_offset: Offset;
        let mut new_root: Node;
        let mut root = Node::try_from(root_page)?;
        if self.is_node_full(&root)? {
            // split the root creating a new root and child nodes along the way.
            new_root = Node::new(NodeType::Internal(vec![], vec![]), true, None);

nimrodshn

/// Implement TryFrom<Page> for Node allowing for easier
/// deserialization of data from a Page.
impl TryFrom<Page> for Node {
    type Error = Error;
    fn try_from(page: Page) -> Result<Node, Error> {
        let raw = page.get_data();
        let node_type = NodeType::from(raw[NODE_TYPE_OFFSET]);
        let is_root = raw[IS_ROOT_OFFSET].from_byte();
        let parent_offset: Option<Offset>;

nimrodshn

PSQL

Magic words:

psql -U postgres

If run with -E flag, it will describe the underlaying queries of the \ commands (cool for learning!).

Most \d commands support additional param of __schema__.name__ and accept wildcards like *.*

nimrodshn

Simple script that plots rarefaction curve from a givenn data set using the following: http://en.wikipedia.org/wiki/Rarefaction_(ecology)

nimrodshn

'''
@param string: input file name with '.xlsx' ending
@author: Nimrod Shneor
'''

import numpy as np
import matplotlib.pyplot as plt
import xlrd
import matplotlib.cm as cm