querqle 0.1.2

A small library made to perform sql queries thru the odbc-api library, and convert the results directly into data structures.
Documentation 
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//wrapper for odbc_api connection, implements limited methods but allows the passing of a odbc_api connection directly
//Goal: Create a connection that can then have queries enter into it and return a result struct which contains a vec<vec<string>> of responses and a vec<string> of column names
use crate::QueryResult;

use odbc_api::Cursor;
use odbc_api::ResultSetMetadata;
use std::error::Error;

///
pub struct Connection<'a> {
    connection: odbc_api::Connection<'a>,
}
impl Connection<'_>{
    ///Executes a command on the connected database. Should only be used to do one command. If 
    ///multiple are used the returned QueryResult will be empty
    pub fn execute_query(&self, query_string: &str) -> Result<QueryResult, Box<dyn Error>> {
        match self.connection.execute(query_string, (), None) {
            Ok(Some(mut cursor)) => {
                let colnames: Vec<String> = cursor.column_names()?.collect::<Result<_, _>>()?;
                let mut table: Vec<Vec<String>> = Vec::new();
                while let Some(mut row) = cursor.next_row()? {
                    let mut row_data: Vec<String> = Vec::new();
                    for i in 1..colnames.len() + 1 {
                        let mut buf = Vec::new();
                        row.get_text(i as u16, &mut buf)?;
                        let val = String::from_utf8_lossy(&buf).to_string();
                        row_data.push(val);
                    }
                    table.push(row_data);
                }
                Ok(QueryResult::new(table, colnames))
            }
            Err(e) => Err(Box::new(e)),
            Ok(None) => Ok(QueryResult::new(Vec::new(),Vec::new())),
        }
    }
    pub(crate) fn new<'a>(connection: odbc_api::Connection<'a>)-> Connection::<'a> {
        Connection{connection}
    }
    //Execute a series of queries and get a vector of their results. 
    pub fn execute_queries(&self, query_strings: Vec<&str>) -> Result<Vec<QueryResult>, Box<dyn Error>> {
        let mut results:Vec<QueryResult>= Vec::new();
        for q_str in query_strings {
            match self.execute_query(q_str) {
                Ok(result) => {
                    results.push(result);
                },
                Err(e) => return Err(e),
            }
        }
        return Ok(results);
    }
}