isCOBOL Evolve : Language Reference : Embedded SQL Statements : DESCRIBE
DESCRIBE
The DESCRIBE statement allows you to obtain information about parameters and other features of a prepared object before you execute it.
Format 1
EXEC SQL [ AT Database ]
 
  DESCRIBE { BIND VARIABLES  } FOR Prepared-Statement INTO { BNDDSC }
           { SELECT LIST     }                             { SELDSC }
 
END-EXEC
Format2
EXEC SQL [ AT Database ]
 
  DESCRIBE { INPUT  } Prepared-Statement INTO Sql-Descriptor
           { OUTPUT } 
 
END-EXEC
Syntax rules
Format 1
1. BNDDSC and SELDSC are group items defined in the Oracle Pro*COBOL SQLDA implementation.
2. Prepared-Statement is a Nonnumeric Literal, as defined in the Definitions section of the Preface of this document.
Format 2
3. The -csdb2 Compiler option must be used in order to compile this statement.
4. Prepared-Statement is a Nonnumeric Literal, as defined in the Definitions section of the Preface of this document.
5. Sql-Descriptor is the group item that identifies the IBM DB2 SQLDA implementation.
General rules
1. Database identifies the active connection that will execute the query and must be previously defined using a Format 4 DECLARE statement. By default, when the AT clause is used, the active connection is switched to the connection identified by Database and all the next statements will work on that connection; under the -csora option, instead, the connection is switched only for the current statement.
Format 1
2. DESCRIBE BIND VARIABLES puts descriptions of bind variables into a bind descriptor. It must follow the PREPARE statement but precede the OPEN.
3. DESCRIBE SELECT LIST puts descriptions of select-list items into a select descriptor. It must follow the OPEN statement but precede the FETCH statement.
Format 2
4. The input INPUT keyword lets you receive information about input parameters.
5. The input OUTPUT keyword lets you receive information about output parameters.
Examples
Prepare a command and get information about it in compatibility with IBM DB2
exec sql
   prepare cmd from "select c1 from tbl where c1 = ?"
end-exec.
exec sql describe input cmd into :sqlda end-exec.