General Rules for Embedding SQL

Location of SQL Commands

Put SQL commands, including their prefix, within columns 7 through 72 of either the main program unit or a subprogram unit:

Prefix

Precede each SQL command with the prefix EXEC SQL. Minimally the prefix must be specified on the same line. For example, the following are legal:

     EXEC SQL SELECT PartName INTO :PartName

    1     FROM PurchDB.Parts WHERE PartNumber = :PartNumber



     EXEC SQL

    1           SELECT PartName

    2           INTO  :PartName

    3           FROM   PurchDB.Parts

    4           WHERE  PartNumber = :PartNumber

However, the following is not legal:

     EXEC

    1    SQL SELECT PartName INTO :PartName

    2        FROM PurchDB.Parts WHERE PartNumber = :PartNumber

FORTRAN Comments

You may insert FORTRAN comment lines within or between embedded SQL commands. Denote comment lines by placing the letter C in column 1 and entering the comment in columns 7 through 72:

         EXEC SQL SELECT PartNumber, PartName

   C     put the data into the following host variables

        1  INTO :PartNumber, :PartName

   C     find the data in the following table

        2  FROM PurchDB.Parts

   C     retrieve only data that satisfies this search condition

        3  WHERE PartNumber = :PartNumber

SQL Comments

SQL comments can be inserted in any line of an SQL statement, except the last line, by prefixing the comment character with at least one space followed by two hyphens followed by one space:

EXEC SQL SELECT * FROM PurchDB.Parts   -- This code selects Parts Table values.

	 WHERE SalesPrice > 500.;

The comment terminates at the end of the current line. (The decimal point in the 500 improves performance when being compared to SalesPrice, which also has a decimal; no data type conversion is necessary.)

Continuation Lines

The FORTRAN preprocessor allows you to continue a non-numeric literal from one line to the next. Enter any character other than the digit 0 or a blank in column 6, and do not enter the character C, *, or $ in column 1. The FORTRAN preprocessor supports up to 19 continuation lines. The the FORTRAN/XL compiler allows you to extend the number of continuation lines, the FORTRAN compiler on other systems where the preprocessor is used does not allow more than 19 contination lines. Therefore, for consistency, the preprocessor only allows 19 contination lines.

      IF (PREDEFINEDCOMMENT .EQ. '5') THEN

          EXEC SQL INSERT INTO PURCHDB.VENDORS

     1      (VendorRemarks)

     2      VALUES ('This vendor is bad news.  Definitely place

     3          no orders.')

      ELSE

          EXEC SQL INSERT INTO PURCHDB.VENDORS

     1      (VendorRemarks)

     2      VALUES (:VendorRemarks)

      ENDIF