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Oracle Built−in Packages- P26

Oracle Built−in Packages- P26: Ah, for the good old days of Version 1.0 of PL /SQL! Life was so simple then. No stored procedures or functions and certainly no packages. You had your set of built−in functions, like SUBSTR and TO_DATE. You had the IF statement and various kinds of loops. With these tools at hand, you built your batch−processing scripts for execution in SQL*Plus, and you coded your triggers in SQL*Forms 3.0, and you went home at night content with a good day's work done. | Appendix A What s on the Companion Disk 2.5.4.7 Build those utilities I suppose you could read this section and shrug thinking Well I don t feel like I have the time to write these kinds of generic utilities. I urge you to reject this line of reasoning. You always have time to create a more generic generally useful implementation. Any time you spend up-front to craft high-quality well-designed modules will pay off for you personally and for all others who benefit from your labors. PL SQL offers endless possibilities for building reusable code which will save you many hours of development debugging and maintenance. The DBMS_SQL package in particular is a veritable gold mine. Dive in and try your hand at dynamic SQL 2.5.4.8 Full text of intab procedure Because the full intab procedure is so long I haven t included it here. For the full text of this procedure see the intab.sp file on the companion disk. 2.5.5 Indirect Referencing in PL SQL I cut my teeth so to speak with Oracle software on a product called SQL Forms. Back around 1987-1989 it was a really hot product for application development and I was a guru. I wrote recursive triggers. I wrote a debugger for this product so thoroughly lacking in a debugger. I could produce robust forms in little or no time. It was very sad then for many of us when Windows and other GUIs came along and Oracle Corporation did not keep up. Of course Oracle Forms has come a long way and is competing well with PowerBuilder and SQL Windows and Visual Basic. That makes me happy because it has some really neat features one of which is indirect referencing. Oracle Forms offers two built-ins the NAME_IN function and the COPY procedure which allow you to retrieve and set by name the values of variables inside your form. For example I can set the value of the global variable GLOBAL.right_now to SYSDATE with the following call COPY TO_CHAR SYSDATE global.right_now and I can retrieve the value of that same global with a call to NAME_IN v_date .