Create a sql table

Tables are used to store data in a database. Tables are named separately within the database and schema. Each table contains one or more columns. And each column has a corresponding type of data that describes the type of data I can save e.g. , numbers, strings, or temporary data.

To create a new table, use the CREATE TABLE statement as follows:

CREATE TABLE SQL keyword. You should always have it at the beginning of your SQL statement. Next, the word new_table_ will become your newly created table name. It can be anything you like. I recommend coming up with a simple and clear word. I also suggest the use of small words. (It doesn't matter though; our current SQL setup doesn't take into account the table names. But I think it's nice and bright that way.) first_ column, second_ column, last column, etc. It will be the names of the new columns in the new table. The same applies to them with regard to the new_table_table: simple and logical words in lower case.

And here comes the trick - or at least one thing - for each column, you have to specify the type of data. As you can see, behind the first_column there is the first_column_data_type. This could be Text, for example. But if you want to fill in the numbers and do the math in them in the future, you should choose the types of numerical data (e.g. number or decimal) instead. Or if you want to use data time functions you must use data / data time types (e.g. Date, Time or Timestamp).Ad Link

Example:



CREATE TABLE < Table Name >

( Column1 DataType,

Column2 DataType,

Column3 DataType

… );



There are some restrictions we can add behind the data to enlarge the columns:

• NOT NULL - moving this parameter will ensure that the column cannot hold the NULL value.

• UNIQUE - passing this parameter will prevent the column from holding more than one volume.

• FIRST KEY - passing this parameter will select that column as a separate identifier. By a combination of the previous two parameters.



Example:



CREATE TABLE planet (

num INT NOT NULL,

name TEXT NOT NULL,

base_mass INT NOT NULL,

power INT NOT NULL

);

Create a Table From an Existing Table:

It is also possible to create a new table based on an existing table.
It's very simple and doesn't require that extra syntax. We need to select a table and columns to "copy" from:

CREATE TABLE new_table_name AS SELECT column1, column 2, column3, column4 (use * to select all columns to be added to new_table) FROM current_table_name WHERE_ situations



Example:



SELECT

id,

name,

rose

INTO florist

FROM product

WHERE category= 'flower';