DESCRIBE statement [Interactive SQL]

Returns information about a given database object.

Syntax 1 - Describing database objects

DESCRIBE [ [ INDEX FOR ] TABLE | PROCEDURE ] [ owner.]object-name

 object-name : 
table
| view
| materialized view
| procedure
| function

Syntax 2 - Describing the current connection

DESCRIBE CONNECTION

Parameters

INDEX FOR clause Indicates that you want to see the indexes for the specified object-name.
TABLE clause Indicates that object-name to be described is a table or a view.
PROCEDURE clause Indicates that object-name is a procedure or a function.

Remarks

Use DESCRIBE TABLE to list all the columns in the specified table or view. The DESCRIBE TABLE statement returns one row per table column, containing:

Column The name of the column.
Type The type of data in the column.
Nullable Whether nulls are allowed (1=yes, 0=no).
Primary Key Whether the column is in the primary key (1=yes, 0=no).

Use DESCRIBE INDEX FOR TABLE to list all the indexes for the specified table. The DESCRIBE TABLE statement returns one row per index, containing:

Index Name The name of the index.
Columns The columns in the index.
Unique Whether the index is unique (1=yes, 0=no).
Type The type of index. Possible values are: Clustered, Statistic, Hashed, and Other.

Use DESCRIBE PROCEDURE to list all the parameters used by the specified procedure or function. The DESCRIBE PROCEDURE statement returns one row for each parameter, containing:

Parameter The name of the parameter.
Type The data type of the parameter.
In/Out Information about what is passed to, or returned from, the parameter. Possible values are:
- In The parameter is passed to the procedure, but is not modified.
- Out The procedure ignores the parameter's initial value and sets its value when the procedure returns.
- In/Out The parameter is passed to the procedure and the procedure sets the parameter's value when the procedure returns.
- Result The parameter returns a result set.
- Return The parameter returns a declared return value.

If you do not specify either TABLE or PROCEDURE (for example, DESCRIBE object-name), Interactive SQL assumes the object is a table. However, if no such table exists, Interactive SQL attempts to describe the object as either a procedure or a function.

Use Syntax 2 to list information about the database or database server that Interactive SQL is connected to. The following properties are returned:

Database Product The name and version number of the database product Interactive SQL is connected to (for example, SQL Anywhere 12.0.1.3600).
Host Name The network name of the computer the database server is running on.
Host TCP/IP Address The IP address of the computer the database server is running on.
Host Operating System The name and version number of the operating system used by the computer the database server is running on.
Server Name The name of the database server.
Server TCP/IP Port The port number used by the database server for the current connection.
Database Name The name of the database that Interactive SQL is connected to.
Database Character Set The character set used for CHAR columns in the database.
Connection String The connection string that was used to connect to the database or database server. Three asterisks replace passwords.

Properties that do not apply to the current connection are omitted. For example, if you connect to a database server using shared memory, then the TCP/IP port is omitted.

DESCRIBE TABLE Departments;

Here is an example of the result set for this statement:

Column	Type	Nullable	Primary key
DepartmentID	integer	0	1
DepartmentName	char(40)	0	0
DepartmentHeadID	integer	1	0

List the indexes for the Customers table:

DESCRIBE INDEX FOR TABLE Customers;

Here is an example of the results for this statement:

Index Name	Columns	Unique	Type
IX_customer_name	Surname,GivenName	0	Clustered

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