shsql: tables organized hierarchically

SQL database system
| Manual page for Tables(organized)

## Tables organized hierarchically

Hierarchical structures are sometimes useful. To accomodate this, shsql allows for collections of data tables to be organized hierarchically.`` The tables in the hierarchy can all share the same format, or have different formats.`` See also the shsql table types chart.``

A hierarchy is created by making a subdirectory in the database `data` directory.`` Data table files can then be created in the subdirectory using CREATE TABLE.`` Table names are relative to the `data` directory.`` For example, after you make a directory in your `data` directory called `cases`, you can issue this CREATE command:

    	create table cases/2002_03 ( field1, field2 .. fieldn )

These data files may be referenced similarly in SQL `SELECT`, `INSERT`, `DELETE`, and `UPDATE` commands, like this:

`select * from cases/2002_03`

To concatenate multiple files from the hierarchy together for treatment as a single table, CREATE STREAM can be used along with dbcat(1).``

## Example

An example of a hierarchical collection of tables is included in `sqlexampledb`.`` See `testruns/README`.``
Copyright Steve Grubb

Markup created by unroff 1.0, `` `` March 18, 2004.