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This is a very useful feature of the database. You can verify if your table has been created successfully using \d command, which will be used to list down all the tables in an attached database. SQL allows you to create a table based on a SELECT statement. Let us create one more table, which we will use in our exercises in subsequent chapters − The following is an example, which creates a COMPANY table with ID as primary key and NOT NULL are the constraints showing that these fields cannot be NULL while creating records in this table − The syntax will become clear with an example given below. Temporary tables are session scoped (similar to Postgres for example).

Then, in brackets, comes the list, defining each column in the table and what sort of data type it is. Temporary tables can be created using a CREATE TEMP TABLE statement (see diagram below). Initially, the empty table in the current database is owned by the user issuing the command. The unique name or identifier for the table follows the CREATE TABLE statement. CTAS is the simplest and fastest way to create and insert data into a table with a single command. CTAS is a parallel operation that creates a new table based on the output of a SELECT statement. Syntaxīasic syntax of CREATE TABLE statement is as follows −ĬREATE TABLE is a keyword, telling the database system to create a new table. The CREATE TABLE AS SELECT (CTAS) statement is one of the most important T-SQL features available. The column names of the new table are defined by the column aliases used in th query. The PostgreSQL CREATE TABLE statement is used to create a new table in any of the given database. 2 Answers Sorted by: 61 It's as easy as: create table newtable as select t1.col1, t2.col2 from sometable t1 join t2 on t1.id t2.someid You can use any select statement for that.