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This is one of at least two ways to create a table only if it doesn’t exist in Oracle. We then only run the CREATE TABLE statement if it doesn’t already exist. Here, we checked the DBA_TABLES data dictionary view to see if the table already exists. One option is to check the DBA_TABLES data dictionary view: DECLARE In that case, if you just remove the if not exists from your create statement, the command will return 1 (indicating failure) if the table exists. It does not return an error, but should not result in a new table of the same name. Oracle Database doesn’t support the CREATE TABLE IF NOT EXISTS statement either, so we also need to use a different method with Oracle. According to the sqlite specification, the ‘IF NOT EXISTS’ clause in the sql statement prevents sql from creation a double of a existing table with the same name. The schemaname option represents the name of the schema in which the table is created. If the table with the given name exists, then it does not create it. The IF NOT EXISTS option checks if the table exists in the SQLlite database. This is one of at least two methods for creating a table only if it doesn’t exist in SQL Server. Creating a table in the SQLite databasebegins with the command CREAE TABLE, followed by the name of the table. Therefore, we can check for a NULL value, and only create the table if this function returns NULL. The sample app uses an SQLite database table to store todo items. If the object doesn’t exist, or if we don’t have access to it, the function returns NULL. First, prepare a CREATE TABLE statement to create the table you want. The OBJECT_ID() returns the database object identification number of a schema-scoped object. In this case we use U, which is for “user defined table”. The second argument specifies the type of object we’re looking for. In this example we’re checking the object ID of a dbo.t1 table. One option is to use the OBJECT_ID() function to check for the existence of the table before we try to create it: IF OBJECT_ID(N'dbo.t1', N'U') IS NULL SQL Server doesn’t support the CREATE TABLE IF NOT EXISTS statement, so we need to use another option. The CREATE TABLE IF NOT EXISTS statement isn’t supported by SQL Server or Oracle (at least not at the time of writing), but we can use one of the methods below. The CREATE TABLE IF NOT EXISTS statement can be used with RDBMSs such as MySQL, MariaDB, PostgreSQL, and SQLite. In this case, the table will only be created if there isn’t already one called t1. Here, t1 is the table name, and everything between the parentheses is the table definition (i.e. Many RDBMSs support the IF NOT EXISTS clause of the CREATE TABLE statement which makes it easy to create a table only when it doesn’t already exist.

Here are some examples of doing this in various RDBMSs. Syntax: CREATE TABLE databasename.tablename ( column1 datatype PRIMARY KEY (one or more columns), column2 datatype, column3 datatype. Doing this prevents any errors from occurring in the event that the table already exists. To create a new table, the CREATE TABLE statement is used in SQLite. When creating a table with SQL, we can specify that the table is only to be created if it doesn’t already exist.