Below are five ways to check if a table exists in a PostgreSQL database.
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Create a Table Only if it Doesn’t Exist in MariaDB
In MariaDB, you can use the IF NOT EXISTS clause of the CREATE TABLE statement to check whether or not a table of the same name already exists in the database before creating it.
The table will only be created if there isn’t already one with the same name.
Continue readingHow to Create a Table Only if it Doesn’t Exist in PostgreSQL
In PostgreSQL, you can use the IF NOT EXISTS clause of the CREATE TABLE statement to check whether or not a table of the same name already exists in the database before creating it.
The table will only be created if no other table exists with the same name. If a table already exists with that name, a “notice” will be issued instead of an error.
Continue readingHow to Check if a Table Already Exists Before Creating it in MySQL
In MySQL, you can use the IF NOT EXISTS clause of the CREATE TABLE statement to check whether or not a table of the same name already exists in the database.
If the table doesn’t exist, it will be created. If it already exists, it won’t be created.
Continue reading5 Ways to Check if a Table Exists in MySQL
Here are five ways to check whether or not a table exists in a MySQL database.
Continue readingAdd a Column to a Table in SQL
In SQL, you can use the ALTER TABLE statement to add one or more columns to an existing table.
To do this, use the ADD clause, followed by the column definition. Separate multiple columns with a comma.
Only specify ADD once (i.e. there’s no need to specify it for each column).
SQL DROP TABLE for Beginners
In SQL, if you want to remove a table from a database, you need to use the DROP TABLE statement.
That destroys the table and all its data.
Continue readingSQLite DROP TABLE
In SQLite, you can drop a table with the DROP TABLE statement.
You can optionally add the IF EXISTS clause to suppress any errors that might occur if the table doesn’t exist.
Also, if the table is referenced by a foreign key, there are a few things to be aware of.
Continue readingSQL ALTER TABLE for Beginners
In SQL, the ALTER TABLE statement modifies the definition of an existing table.
You can use ALTER TABLE to alter, add, or drop columns and constraints.
Depending on your DBMS, the ALTER TABLE statement can also be used to reassign and rebuild partitions, or disable and enable constraints and triggers.
Create a Partitioned Table in SQL Server (T-SQL)
SQL Server supports partitioned tables and indexes. When a partitioned table or index is partitioned, its data is divided into units that can be spread across more than one filegroup.
Therefore, to create a partitioned table in SQL Server, you first need to create the filegroup/s that will hold each partition. You also need to create a partition function and a partition scheme.
So it goes like this:
- Create filegroup/s
- Create a partition function
- Create a partition scheme
- Create the partitioned table
Below is an example of using these steps to create a table with four partitions.
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