What does desc mean in oracle

DESC (DESCRIBE) command is used to describe the structure of a table or view in an Oracle database, providing information about columns, data types, size, nullability, and other details. The specific steps are as follows: Use syntax: DESC table_name; Return information: column name, data type, size, nullability, default value, constraints.

#What does desc mean in oracle?

DESC (DESCRIBE) command is used to describe the structure of a table or view in an Oracle database. It provides information about the columns, data types, size, nullability, and other details of a table or view.

Use the syntax

DESC table_name;

wheretable_nameis the name of the table or view to be described.

Return information

The DESC command returns the following information about the table or view:

• Column name: table column names in .
• Data type: The data type of each column (such as VARCHAR2, NUMBER, DATE).
• Size: The maximum amount of data that can be stored in each column.
• Nullable: Indicates whether the column allows null values (YES or NO).
• Default value: The default value of the column, NULL if not specified.
• Constraints: Any constraints applied to the column (such as NOT NULL, UNIQUE, PRIMARY KEY).

Example

The following example describes theemployeestable:

DESC employees;

The output will look like this:

Column Name Data Type Length Nullable Default Primary/Foreign Key --------------------- -------------------- -------- -------- ---------- --------------- employee_id NUMBER 22 NO first_name VARCHAR2 25 YES NULL last_name VARCHAR2 25 YES NULL email VARCHAR2 255 NO NULL phone_number VARCHAR2 20 YES NULL hire_date DATE 7 NO NULL job_id VARCHAR2 10 NO NULL salary NUMBER 22 YES NULL manager_id NUMBER 22 YES NULL department_id NUMBER 22 YES NULL 

This output shows the detailed structure of the columns in theemployeestable, including data type, size, nullability, default value, and any constraints.

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