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52 lines
1.4 KiB
52 lines
1.4 KiB
# Create Table |
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The `CREATE TABLE` statement in SQL is a Data Definition Language (DDL) command used to create a new table in the database. |
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## SQL CREATE TABLE Syntax |
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The syntax for SQL `CREATE TABLE` is as follows: |
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```sql |
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CREATE TABLE table_name ( |
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column1 datatype, |
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column2 datatype, |
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column3 datatype, |
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.... |
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); |
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``` |
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- `table_name` is the name of the table that you want to create. |
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- `column1, column2,...` are the columns in the table. |
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- `datatype` is the data type for the column, such as varchar, int, date, etc. |
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## SQL CREATE TABLE Example |
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Here is an example of the `CREATE TABLE` statement: |
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```sql |
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CREATE TABLE Employees ( |
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ID int, |
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Name varchar(255), |
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Salary int, |
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Department varchar(255), |
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Position varchar(255) |
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); |
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``` |
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This SQL command creates a new table named `Employees` with five columns, named 'ID', 'Name', 'Salary', 'Department', and 'Position'. The data types are int for the 'ID' and 'Salary', and varchar(255) for the others. |
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## SQL CREATE TABLE with NOT NULL |
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The `NOT NULL` constraint enforces a column to not accept null values. When creating a new table, you can add this constraint. Here is a practical example: |
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```sql |
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CREATE TABLE Employees ( |
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ID int NOT NULL, |
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Name varchar(255) NOT NULL, |
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Salary int, |
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Department varchar(255), |
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Position varchar(255) |
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); |
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``` |
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In the example above, the 'ID' and 'Name' must always have a value. They cannot be unassigned or undefined. |