Dump sql server database to file
The idea behind this dump method is to generate a text file with SQL commands that, when fed back to the server, will recreate the database in the same state as it was at the time of the dump.
The basic usage of this command is:. Anyone have any pointers on importing SQL dump files into R? Each line has a ton of records. The easy answer comes by reading the file. It's a text file, not binary, so you should be able to glean what it is by just opening it up in Wordpad Notepad can't open such large files.
More than likely it's a complete dump of all the data in the database, in one big SQL query. We will see below how this can be useful. This means that you can perform this backup procedure from any remote host that has access to the database. In particular, it must have read access to all tables that you want to back up, so in practice you almost always have to run it as a database superuser. Similarly, the default port is indicated by the PGPORT environment variable or, failing that, by the compiled-in default.
Conveniently, the server will normally have the same compiled-in default. To do this, use the -o command-line option. The general command form to restore a dump is. The database dbname will not be created by this command, so you must create it yourself from template0 before executing psql e. See the psql reference page for more information. Before restoring an SQL dump, all the users who own objects or were granted permissions on objects in the dumped database must already exist.
Sometimes this is what you want, but usually it is not. By default, the psql script will continue to execute after an SQL error is encountered. Either way, you will only have a partially restored database. Alternatively, you can specify that the whole dump should be restored as a single transaction, so the restore is either fully completed or fully rolled back. This mode can be specified by passing the -1 or --single-transaction command-line options to psql.
When using this mode, be aware that even a minor error can rollback a restore that has already run for many hours. However, that might still be preferable to manually cleaning up a complex database after a partially restored dump.
This means that any languages, procedures, etc. As a result, when restoring, if you are using a customized template1 , you must create the empty database from template0 , as in the example above. For more advice on how to load large amounts of data into PostgreSQL efficiently, refer to Section Actually, you can specify any existing database name to start from, but if you are loading into an empty cluster then postgres should usually be used.
If you use tablespaces, make sure that the tablespace paths in the dump are appropriate for the new installation. Whereas, DatabaseFirst approach is used for existing physical schema whcih is probably already designed and optimized. A DbSet represents the collection of all entities in the context, or that can be queried from the database, of a given type.
Set method. Creating a. There is the Entity Connection. Choose the Categories table and select this one. The model will be generated and opened in the EDM Designer. Database First allows you to reverse engineer a model from an existing database. The model is stored in an EDMX file. The classes that you interact with in your application are automatically generated from the EDMX file.
There is no edmx support in Entity Framework Core. It only supports a code-first approach. The option to add a new Entity Data Model will be added, but it will produce entity class files instead of an edmx file. In this example, the log file is written to the directory from which the dump file is read, but it can be written to a different location. After this statement executes successfully, check the import log file to ensure that no unexpected error has occurred.
When dealing with a large number of data files, specifying the list of data file names in the statement line can be a laborious process. It can even exceed the statement line limit. In this situation, you can use an import parameter file. For example, you can invoke the Data Pump import utility as follows:. Ensure that no user changes are made to the data during the import.
For example, if the connect identifier for the PDB is hrpdb , then enter the following when you run the Oracle Data Pump Import utility:. Oracle Database Utilities for information about using the import utility.
Oracle Multitenant Administrator's Guide. Parent topic: Migrating Oracle Database. Previous Next JavaScript must be enabled to correctly display this content. You can transport a database using an export dump file.
Transport the export dump file. Copy the export dump file to a place that is accessible to the target database. Transport the data files for all of the user-defined tablespaces in the database.
Copy the data files to a place that is accessible to the target database.
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