*Action: Only the objects in RecycleBin can be Flashback Dropped. *Cause: Trying to Flashback Drop an object which is not in RecycleBin. DROP TABLE table4 PURGE įLASHBACK TABLE table4 TO BEFORE DROP SQL Error: ORA-38305: object not in RECYCLE BINģ8305. Let’s delete a table using PURGE and try to restore it. We can see that the table has been restored and the data is now viewable. Read more on this error here: ORA-00942 error. It shows an error because the table has been dropped. SELECT COUNT(*) FROM table3 ORA-00942: table or view does not exist This shows us that we have a table and what’s inside it. DROP TABLE table2 CASCADE CONSTRAINTS Table TABLE1 dropped. Let’s try it again with CASCADE CONSTRAINTS. You can see whatĬonstraints are referencing a table by issuing the following *Action: Before performing the above operations the table, drop theįoreign key constraints in other tables. Primary keys referenced by foreign keys in another table. *Cause: An attempt was made to drop a table with unique or 00000 - "unique/primary keys in table referenced by foreign keys" This example drops a table that has constraints. This statement drops a table which has no constraints.
Here are some examples of dropping deleting a table in Oracle SQL. Oracle does not include this as part of the DROP TABLE keyword. Some databases support the SQL drop table if exists feature: MySQL, SQL Server, and PostgreSQL. The DELETE statement deletes rows from a table and is specified as DELETE FROM TABLE. I’ll write more about the FLASHBACK command in another post. FLASHBACK TABLE tablename TO BEFORE DROP You can undo the deleting of a table in Oracle SQL by using the FLASHBACK command.
Drop databse with tableplus free#
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. What Happens When You Drop a Table in a Database?.What Does the DROP TABLE Statement Look Like?.
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