All extents allocated for the table are returned to the free space of the tablespace and can be used by other objects if required.All views and PL/SQL program units that depend on this table will remain, but they become invalid.All synonyms that point to this table remain, but when you try to use them, you’ll get an error.All indexes and triggers on the table are dropped.The table is no longer in the data dictionary.The data is removed and is no longer accessible.There are a few things that happen in Oracle when you drop a table: What Happens When You Drop a Table in a Database? RESTRICT: Refuse to drop the table if any objects depend on it.CASCADE: Automatically drop objects that depend on the table (such as views) and then all objects that depend on those objects.There are two parameters at the end of the statement: You can also drop multiple tables with a single statement in PostgreSQL. PostgreSQL also includes an IF EXISTS keyword to run the command only if the table exists. If you want to drop all tables in a database, I’ve written about several methods to do that here: MySQL Drop All Tables: How-To With Examples If you want to remove the constraints that impact this table, you’ll need to drop the constraints first, then drop the table. They don’t actually do anything, and just exist to make porting to other databases easier. There are two additional options at the end of the statement: RESTRICT and CASCADE. You can also drop multiple tables with a single statement in MySQL. You can drop a temporary table by using the TEMPORARY keyword. MySQL lets you use the IF EXISTS keyword to run the command only if the table exists. You’ll need to drop the constraints first, then drop the table. There is no CASCADE keyword for SQL Server. You can also specify the database name and schema name, but they are not required. SQL Server lets you drop multiple tables in one command. The IF EXISTS keyword lets you only run the command if the table exists. By default, this is not specified, and the table and objects are moved to the recycle bin and can be recovered if you need to. If you specify PURGE, it means that the table and its dependent objects will be purged from the recycle bin, and you will no longer be able to recover the table. If there are constraints on the table and you don’t specify this keyword, then an error will be displayed and the table will not be dropped. The CASCADE CONSTRAINTS keyword means that all referential integrity constraints with the table will be dropped as well. The syntax for the DROP TABLE command is pretty simple: DROP TABLE tablename įirst, you write DROP TABLE, and then the name of the table you want to drop.Įach database has its own additions to the SQL DROP TABLE statement. What Does the DROP TABLE Statement Look Like? The DELETE keyword is used when you want to delete data from a table (or materialized view). It’s called DROP because that’s the standard term for deleting objects from a database. To delete a table in SQL, you run a statement called DROP TABLE.
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