In this chapter, you will learn how to roll back the un-committed transaction through the OrientDB command line interface.

The following statement is the basic syntax of the Rollback database command.

ROLLBACK

Note − You can use this command only after connecting to a particular database and after beginning the transaction.

Example

In this example, we will use the same database named ‘demo’ that we created in the previous chapter. We will see the operation of rollback transaction and store a record using transactions.

First, start the transaction using the following BEGIN command.

orientdb {db = demo}> BEGIN

Then, insert a record into an employee table with the values id = 12 and name = satish.P using the following command.

orientdb> INSERT INTO employee (id, name) VALUES (12, ''satish.P'')

You can use the following command to retrieve the records from the Employee table.

orientdb> SELECT FROM employee WHERE name LIKE ''%.P''

If this command is executed successfully, you will get the following output.

---+-------+--------------------
 # | ID   | name
---+-------+--------------------
 0 | 12   | satish.P
---+-------+--------------------
1 item(s) found. Query executed in 0.076 sec(s).

You can now use the following command to Rollback this transaction.

orientdb> ROLLBACK

Check the select query again to retrieve the same record from the employee table.

orientdb> SELECT FROM employee WHERE name LIKE ''%.P''

If the rollback is executed successfully, you will get 0 records found in the output.

0 item(s) found. Query executed in 0.037 sec(s).

Similar to RDBMS, OrientDB provides the feature to drop a database. Drop database refers to removing a database completely.

The following statement is the basic syntax of the Drop database command.

DROP DATABASE [<database-name> <server-username> <server-user-password>]

Following are the details about the options in the above syntax.

<database-name> − Database name you want to drop.

<server-username> − Username of the database who has the privilege to drop a database.

<server-user-password> − Password of the particular user.

Example

There are two ways to drop a database, one is drop a currently open database and second is drop a particular database by providing the particular name.

In this example, we will use the same database named ‘demo’ that we created in an earlier chapter. You can use the following command to drop a database demo.

orientdb {db = demo}> DROP DATABASE

If this command is successfully executed, you will get the following output.

Database ''demo'' deleted successfully

OR

You can use another command to drop a database as follows.

orientdb> DROP DATABASE PLOCAL:/opt/orientdb/databases/demo admin admin

If this command is successfully executed, you will get the following output.

Database ''demo'' deleted successfully

Similar to RDBMS, OrientDB also provides transaction concepts like Commit and Rollback. Commit refers to closing the transaction by saving all changes to the database. Rollback refers to recovering the database state to the point where you opened the transaction.

The following statement is the basic syntax of the Commit database command.

COMMIT

Note − You can use this command only after connecting to a particular database and after beginning the transaction.

Example

In this example, we will use the same database named ‘demo’ that we created in the previous chapter. We will see the operation of commit transaction and store a record using transactions.

First, start the transaction using the following BEGIN command.

orientdb {db = demo}> BEGIN

Then, insert a record into an employee table with the values id = 12 and name = satish.P using the following command.

orientdb> INSERT INTO employee (id, name) VALUES (12, ''satish.P'')

You can use the following command to commit the transaction.

orientdb> commit

If this transaction is successfully committed, you will get the following output.

Transaction 2 has been committed in 4ms

Whenever you want to import the database, you must use the JSON format exported file, which is generated by export command.

In this chapter you can learn how to import the database from the OrientDB command line.

The following statement is the basic syntax of the Import database command.

IMPORT DATABASE <input file>

Note − You can use this command only after connecting to a particular database.

Example

In this example, we will use the same database named ‘demo’ that we created in the previous chapter. You can use the following command to import the database to a file named ‘export-demo.gz’.

orientdb {db = demo}> IMPORT DATABASE ./export-demo.export.gz

If it is successfully executed, you will get the following output along with the successful notification.

Database import completed in 11612ms

In this chapter, you can learn how to release the database from the freeze state through OrientDB command line.

The following statement is the basic syntax of the Release database command.

RELEASE DATABASE

Note − You can use this command only after connecting to a particular database, which is in freeze state.

Example

In this example, we will use the same database named ‘demo’ that we created in the previous chapter. We will release the database that was freezed in the previous chapter.

You can use the following command to release the database.

Orientdb {db = demo}> RELEASE DATABASE

If it is successfully executed, you will get the following output.

Database ''demo'' was release successfully

Like RDBMS, OrientDB also provides features like Export and Import the database. OrientDB uses the JSON format to export the data. By default export command is using the GZIP algorithm to compress the files.

While exporting a database it is not locking the database, which means you can perform concurrent read and write operations on it. It also means that you can create an exact copy of that data because of concurrent read and write operations.

In this chapter, you can learn how to export the database from the OrientDB command line.

The following statement is the basic syntax of the Export database command.

EXPORT DATABASE <output file>

Note − You can use this command only after connecting to a particular database.

Example

In this example, we will use the same database named ‘demo’ that we created in the previous chapter. You can use the following command to export the database to a file named ‘export-demo’.

orientdb {db = demo}> EXPORT DATABASE ./export-demo.export

If it is successfully executed, it will create a file named ‘export-demo.zip’ or ‘exportdemo.gz’ based on the operating system and you will get the following output.

Exporting current database to: DATABASE /home/linuxtp/Desktop/demo.export in
GZipped JSON format ...

Started export of database ''demo'' to /home/linuxtp/Desktop/demo.export.gz...
Exporting database info...OK
Exporting clusters...OK (12 clusters)
Exporting schema...OK (11 classes)
Exporting records...
- Cluster ''internal'' (id = 0)...OK (records = 3/3)
- Cluster ''index'' (id = 1)...OK (records = 0/0)
- Cluster ''manindex'' (id = 2)...OK (records = 0/0)
- Cluster ''default'' (id = 3)...OK (records = 0/0)
- Cluster ''orole'' (id = 4)...OK (records = 3/3)
- Cluster ''ouser'' (id = 5)...OK (records = 3/3)
- Cluster ''ofunction'' (id = 6)...OK (records = 0/0)
- Cluster ''oschedule'' (id = 7)...OK (records = 0/0)
- Cluster ''orids'' (id = 8)...OK (records = 0/0)
- Cluster ''v'' (id = 9)...OK (records = 0/0)
- Cluster ''e'' (id = 10)...OK (records = 0/0)
- Cluster ''_studio'' (id = 11)...OK (records = 1/1)

Done. Exported 10 of total 10 records

Exporting index info...
- Index dictionary...OK
- Index OUser.name...OK
- Index ORole.name...OK
OK (3 indexes)
Exporting manual indexes content...
- Exporting index dictionary ...OK (entries = 0)
OK (1 manual indexes)

Database export completed in 377ms

Whenever you want to make the database state as static it means a state where the database didn’t respond to any of the read and write operations. Simply said, the database is in freeze state.

In this chapter, you can learn how to freeze the database from the OrientDB command line.

The following statement is the basic syntax of the freeze database command.

FREEZE DATABASE

Note − You can use this command only after connecting to a particular database either in remote or local database.

Example

In this example, we will use the same database named ‘demo’ that we created in the previous chapter. We will freeze this database from CLI.

You can use the following command to freeze the database.

Orientdb {db = demo}> FREEZE DATABASE

If it is successfully executed, you will get the following output.

Database ''demo'' was frozen successfully

In this chapter, you can learn how to display the configuration of a particular database through OrientDB command line. This command is applicable for both local and remote databases.

Configuration information contains default cache either enabled or not, the size of that cache, the load factor value, max memory for map, node page size, pool minimum and maximum size, etc.

The following statement is the basic syntax of the config database command.

CONFIG

Note − You can use this command only after connecting to a particular database.

Example

In this example, we will use the same database named ‘demo’ that we created in the previous chapter.

You can use the following command to display the configuration of demo database.

Orientdb {db = demo}> CONFIG

If it is successfully executed, you will get the following output.

LOCAL SERVER CONFIGURATION:
+---------------------------------------+-------------------------+
| NAME                                  | VALUE                   |
+---------------------------------------+-------------------------+
| environment.dumpCfgAtStartup          | false                   |
| environment.concurrent                | true                    |
| environment.allowJVMShutdown          | true                    |
| script.pool.maxSize                   | 20                      |
| memory.useUnsafe                      | true                    |
| memory.directMemory.safeMode          | true                    |
| memory.directMemory.trackMode         | false                   |
|………………………………..                         |                         |
| storage.lowestFreeListBound           | 16                      |
| network.binary.debug                  | false                   |
| network.http.maxLength                | 1000000                 |
| network.http.charset                  | utf-8                   |
| network.http.jsonResponseError        | true                    |
| network.http.json                     | false                   |
| tx.log.fileType                       | classic                 |
| tx.log.synch                          | false                   |
| tx.autoRetry                          | 1                       |
| client.channel.minPool                | 1                       |
| storage.keepOpen                      | true                    |
| cache.local.enabled                   | true                    |
+---------------------------------------+-------------------------+
orientdb {db = demo}>

In the above list of configuration parameters, if you want to change any of the parameter value then you can do it from the command line easily using config set and get command.

Config Set

You can update the configuration variable value by using the CONFIG SET command.

The following statement is the basic syntax of the config set command.

CONFIG SET <config-variable> <config-value>

Note − You can use this command only after connecting to a particular database.

Example

In this example, we will use the same database named ‘demo’ that we created in the previous chapter. We will modify the ‘tx.autoRetry’ variable value to 5.

You can use the following command to set the configuration of demo database.

orientdb {db = demo}> CONFIG SET tx.autoRetry 5

If it is successfully executed, you will get the following output.

Local configuration value changed correctly

Config Get

You can display the configuration variable value by using the CONFIG GET command.

The following statement is the basic syntax of the config get command.

CONFIG GET <config-variable>

Note − You can use this command only after connecting to a particular database.

Example

In this example, we will use the same database named ‘demo’ that we created in the previous chapter. We will try to retrieve the ‘tx.autoRetry’ variable value.

You can use the following command to display the configuration of demo database.

orientdb {db = demo}> CONFIG GET tx.autoRetry

If it is successfully executed, you will get the following output.

Local configuration: tx.autoRetry = 5

This chapter explains how to get the list of all databases in an instance from the OrientDB command line.

The following statement is the basic syntax of the info command.

LIST DATABASES

Note − You can use this command only after connecting to a local or remote server.

Example

Before retrieving the list of databases, we have to connect to the localhost server through the remote server. It is required to remind that the username and password for connecting to the localhost instance is guest and guest respectively, which is configured in the orintdb/config/orientdb-server-config.xml file.

You can use the following command to connect to the localhost database server instance.

orientdb> connect remote:localhost guest

It will ask the password. As per the config file password for guest is also guest. If it is successfully connected, you will get the following output.

Connecting to remote Server instance [remote:localhost] with user ''guest''...OK
orientdb {server = remote:localhost/}>

After connecting to the localhost database server you can use the following command to list the databases.

orientdb {server = remote:localhost/}> list databases

If it is successfully executed, you will get the following output −

Found 6 databases:
* demo (plocal)
* s2 (plocal)
* s1 (plocal)
* GratefulDeadConcerts (plocal)
* s3 (plocal)
* sample (plocal)
orientdb {server = remote:localhost/}>

This chapter explains how to get information of a particular database from the OrientDB command line.

The following statement is the basic syntax of the Info command.

info

Note − You can use this command only after connecting to a particular database and it will retrieve the information of only the currently running database.

Example

In this example, we will use the same database named ‘demo’ that we created in the previous chapter. We will retrieve the basic information from demo database.

You can use the following command to disconnect the database.

orientdb {db = demo}> info

If it is successfully disconnected, you will get the following output.

Current database: demo (url = plocal:/opt/orientdb/databases/demo)

DATABASE PROPERTIES
--------------------------------+---------------------------------------------+
 NAME                           | VALUE                                       |
--------------------------------+---------------------------------------------+
 Name                           | null                                        |
 Version                        | 14                                          |
 Conflict Strategy              | version                                     |
 Date format                    | yyyy-MM-dd                                  |
 Datetime format                | yyyy-MM-dd HH:mm:ss                         |
 Timezone                       | Asia/Kolkata                                |
 Locale Country                 | IN                                          |
 Locale Language                | en                                          |
 Charset                        | UTF-8                                       |
 Schema RID                     | #0:1                                        |
 Index Manager RID              | #0:2                                        |
 Dictionary RID                 | null                                        |
--------------------------------+---------------------------------------------+

DATABASE CUSTOM PROPERTIES:
 +-------------------------------+--------------------------------------------+
 | NAME                          | VALUE                                      |
 +-------------------------------+--------------------------------------------+
 | strictSql                     | true                                       |
 +-------------------------------+--------------------------------------------+
CLUSTERS (collections)
---------------------------------+-------+-------------------+----------------+
 NAME                            | ID    | CONFLICT STRATEGY | RECORDS        |
---------------------------------+-------+-------------------+----------------+