mdb-sql

Name

mdb-sql - SQL interface to MDB Tools

Synopsis

mdb-sql [-HFp] [-d <delimiter>] [-i <file>] [-o <file>] [<database>]

Description

mdb-sql is a utility program distributed with MDB Tools.

mdb-sql allows querying of an MDB database using a limited SQL subset language.

Options

-H

Supress header row.

-F

Supress footer row.

-p

Turn off pretty printing. By default results are printed in an ascii table format which looks nice but is not conducive to manipulating the output with unix tools. This option prints output plainly in a tab separated format.

-d

Specify an alternative column delimiter. If no delimiter is specified, columns will be delimited by a tab character if pretty printing (-p) is turned off. If pretty printing is enabled this option is meaningless.

-i

Specify an input file. This option allows an input file containing the SQL to be passed to mdb-sql. See Notes.

-o

Specify an output file. This option allows the name of an output file to be used instead of stdout.

Commands

mdb-sql in interactive mode takes some special commands.

connect to <database>

If no database was specified on the command line this command is necessary before any querys are issued. It also allows the switching of databases once in the tool.

disconnect

Will disconnect from the current database.

go

Each batch is sent to the parser using the 'go' command.

reset A batch can be cleared using the 'reset' command.

list tables

The list tables command will display a list of available tables in this database, similar to the mdb-tables utility on the command line.

describe table <table>

Will display the column information for the specified table.

quit

Will exit the tool.

Sql Language

The currently implemented SQL subset is quite small, supporting only single table queries, no aggregates, and limited support for WHERE clauses. Here is a brief synopsis of the supported language.

select:

SELECT [* | <column list>] FROM <table> WHERE <where clause>

column list:

<column> [, <column list>]

where clause:

<column> <operator> <literal> [AND <where clause>]

operator:

=, =>, =<, <>, like, <, >

literal:

integers, floating point numbers, or string literal in single quotes

Notes

When passing a file (-i) or piping output to mdb-sql the final 'go' is optional. This allow constructs like

echo "Select * from Table1" | mdb-sql mydb.mdb

to work correctly.

The -i command can be passed the string 'stdin' to test entering text as if using a pipe.