4 Ways to Check if a Table Exists Before Dropping it in SQL Server (T-SQL)

Dropping a table in SQL easy. You simply use DROP TABLE myTable where myTable is the name of the table you want to drop. You can use this method to drop a table in SQL Server via T-SQL script.

But you’ll get an error if the table doesn’t actually exist. That is, unless you check for the existence of the table first.

Below are four ways of using T-SQL to check whether the table exists before dropping it.

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How to Create a Table Only if it Doesn’t Exist in SQLite

In SQLite, you can use the IF NOT EXISTS clause of the CREATE TABLE statement to check whether or not a table or view of the same name already exists in the database before creating it.

Creating a table without this clause would normally result in an error if a table of the same name already existed in the database. But when using the IF NOT EXISTS clause, the statement has no effect if a table already exists with the same name.

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How 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.

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Create a Collection in MongoDB

When you create a database in MongoDB, your database is basically an empty container for which you can add one or more collections to.

A collection is analogous to a table in relational databases.

In relational databases, you can use CREATE TABLE to create each table that you want in the database.

But MongoDB is not a relational database, and it stores its data as documents. Each document is stored in a collection.

This article shows you how to create a collection in MongoDB.

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