SDB/Commands

This page describes the command line programs that can be used to create an SDB store, load data into it and to issue queries.

Contents

Scripts

The directory bin/ contains shell scripts to run the commands from the command line. The scripts are bash scripts which also run over Cygwin.

Script set up

Set the environment variable SDBROOT to the root of the SDB installation.

A store description can include naming the class for the JDBC driver. Getting a Store object from a store description will automatically load the JDBC driver from the classpath.

When running scripts, set the environment variable SDB_JDBC to one or more jar files for JDBC drivers. If it is more than one jar file, use the classpath syntax for your system. You can also use the system property jdbc.drivers.

Set the environment variables SDB_USER and SDB_PASSWORD to the database user name and password for JDBC.

 $ export SDBROOT="/path/to/sdb
 $ export SDB_USER="YourDbUserName"
 $ export SDB_PASSWORD="YourDbPassword"
 $ export SDB_JDBC="/path/to/driver.jar"

They are bash scripts, and work on Linux and Cygwin for MS Windows.

 $ export PATH=$SDBROOT/bin:$PATH

Alternatively, there are wrapper scripts in $SDBROOT/bin2 which can be placed in a convenient directory that is already on the shell command path.

Argument Structure

All commands take a SDB store description to extract the connection and configuration information they need. This is written SPEC in the command descriptions below but it can be composed of several arguments as described here.

Each command then has command-specific arguments described below.

All commands support --help to give details of named and positional arguments.

There are two equivalent forms of named argument syntax:

--arg=val

--arg val

Store Description

If this is not specified, commands load the description file sdb.ttl from the current directory.

 --sdb=<sdb.ttl>

This store description is a Jena assembler file. The description consists of two parts; a store description and a connection description.

Often, this is all that is needed to describe which store to use. The individual components of a connection or configuration can be overridden after the description have been read, before it is processed.

The directory Store/ has example assembler files.

The full details of the assembler file is given in ‘SDB/Store Description

Modifying the Store Description

The individual items of a store description can be overridden by various command arguments. The description in the assembler file is read, then any command line arguments used to modify the description, then the appropriate object is created from the modified description.

Set the layout type:

 --layout : layout name

Currently, one of layout1, layout2, layout2/index, layout2/hash.

Set JDBC details:

 --dbName : Database Name
 --dbHost : Host machine name
 --dbType : Database type.
 --dbUser : Database use
 --dbPassword : Database password.

The host name can host or host:port.

The better way to handle passwords is to use environment variables SDB_USER and SDB_PASSWORD because then the user/password is not stored in a visible way.

Logging and Monitoring

All commands take the following arguments (although they may do nothing if they make no sense to the command).

 -v

Be verbose.

 --time

Print timing information. Treat with care - while the timer avoids recording JVM and some class loading time, it can’t avoid all class loading. Hence, the values of timing are more meaningful on longer operations. JDBC operation times to a remote server can also be a significant proportion in short operations.

 --log=[all|none|queries|statements|exceptions]

to log SQL actions on the database connection (but not the prepared statements used by the loader). Can be repeated on the command line.

SDB Commands

Database creation

 sdbconfig SPEC [--create|--format|--indexes|--dropIndexes]

Setup a database.

Option Description
--create formats the store and sets up indexes
--format just formats the store and creates indexes for loading, not querying.
--indexes Create indexes for querying
--dropIndexes  Drop indexes for querying.

Loading large graphs can be faster by formatting, loading the data, then building the query indexes with this command.

 sdbtruncate SPEC

Truncate the store. Non-transactional. Destroys data.

Loading data

 sdbload SPEC FILE [FILE ...]

Load RDF data into a store using the SDB bulk loader. Data is streamed into the database and is not loaded as a single transaction.

The file’s extension is used to determine the data syntax.

To load into a named graph:

 sdbload SPEC --graph=URI FILE [FILE ...]

Query

 sdbquery SPEC --query=FILE

Execute a query.

 sdbprint SPEC --print=X [--sql] --query=FILE

Print details of a query. X is any of query, op, sqlNode, sql or plan. --print=X can be repeated. –sql is short for –print=sql. The default is --print=sql.

Testing

 sdbtest SPEC MANIFEST

Execute a test manifest file. The manifest of all query tests, which will test connection and loading of data, is in <em>SDBROOT</em>/testing/manifest-sdb.ttl.

Other

 sdbdump SPEC --out=SYNTAX

Dump the contents of a store N-TRIPLES or a given serialization format (usual Jena syntax names, e.g. Turtle or TTL).

Only suitable for data sizes that fit in memory. All output syntaxes that do some form of pretty printing will need additional space for their internal datastructures.

 sdbsql SPEC [ --file=FILE | SQL string ]

Execute a SQL command on the store, using the connection details from the store specification. The SQL command either comes from file FILE or the command line as a string.

 sdbinfo SPEC

Details of a store.

 sdbmeta SPEC --out=SYNTAX

Do things with the meta graphs of a store.

 sdbscript SPEC FILE

Execute a script. Currently only JRuby is supported.

 sdbtuple SPEC [--create|--print|--drop|--truncate]  tableName

Many of the tables used within SDB are tuples of RDF nodes. This command allows low-level access to these tuple tables. Misuse of this command can corrupt the store.