More about getting information about SQL Views

Several years ago I wrote a post about the Db2 for i (SQL) Views about Views:

• SYSVIEWS:  Information about Views themselves
• SYSVIEWDEP:  Information about Views' dependencies

One of the things I talk about during presentations I give to Local User Groups, LUG, is the use of SQL Views and how they make my programming simpler. Therefore, I wanted to revisit these two Views and explain how they help me learn more about the Views in the partitions I use.

Before I can show what kinds of information I can get from SYSVIEWS and SYSVIEWSDEP I am going to need some Views to play with.

I am going to join a DDS file, TESTFILE, and a DDL table, TESTTABLE to create my first View. While it is not essential to know what the file and table look like I am just going to include their source code below.

First TESTFILE:

Generate spreadsheet with SQL in batch job

When I wrote about the Db2 for i, or SQL, scalar function to create a Microsoft Excel spreadsheet in the IFS my example program ran interactively. I recently received a message asking the following: "good stuff even though I started to use it, it has some limitations so far: doesn't work with QTEMP files. Am I right?"

I submitted my example program to batch and found that the expected spreadsheet was not generated. Looking in the job's job log I could see several messages related to files I created in QTEMP not being found. It would appear that the Java called by the GENERATE_SPREADSHEET submits a job to batch with the type BATCHI.

If I should not use files in QTEMP then I need a Standard Output file, STDOUT, in another library. I chose to create it in QGPL, but it could be in any library that is in the users' library list. As STDOUT is a source file I create it with the following:

CRTSRCPF FILE(QGPL/STDOUT) RCDLEN(266) + TEXT('Standard output file')

End to free format directive

What I call totally free RPG and what IBM calls modern RPG has been around for nine years. This type of RPG always needs the **FREE directive starting in the first position of the source line. And what follows is the free form RPG, where the source line can start in any position.

...+... 1 ...+... 2 ...+... 3 ...+... 4 ...+... 5 ...+... 6 ...+... 7 ...+... 8 01 **free 02 dcl-s Statement1 varchar(100) inz('Entered in free format RPG') ;

Marc Raynor informed me of another directive that "ends" the free format RPG, **END-FREE. After that directive all valid RPG must be entered in the sixth position for fixed format code, and later for the not completely free format code.

Having been told this I had to try it:

ACS 1.1.9.5 out now

I want to thank Shaker Steven for bringing to my attention this morning that the Spring 2024 update for Access Client Solutions, ACS, is now available. When I opened my ACS the following window popped up informing me the new update was available.

Using Select Into with Execute Immediate

The idea for this post came from a question I was asked about using the Execute Immediate SQL statement. The questioner asked why he was unable to execute a Select Into statement using Execute Immediate. His RPG source code compiled, but when called the program would error with a SQL code of -312, or message id SQL0312:

Variable RESULT not defined or not usable for reason code 8. 8 -- The host variable is specified in dynamic SQL. Host variables are not valid in dynamic SQL. Parameter markers must be used instead.

I found a solution for him. I could resist playing with what I found and created a far more complicated scenario that I am sharing with you in this post.

Patron saint of IT's day

In the western Christian calendar today is a special day for everyone working in information Technology, as it is Saint Isidore of Seville saint's day.

St Isidore of Seville is special to the IT community as in 1997 he was made patron saint of all things related to computers and IT by Pope John Paul II. You can learn more about Isidore here.

Happy St Isidore of Seville day, and let's hope for a little divine intervention so all of our IT projects in the next year complete successfully, on time, and on budget.

"Looking at his example it looks so easy. Gratias tibi RPGPGM.COM!"

Send email with SQL in batch job

When I wrote about the Db2 for i, or SQL, scalar function to create a Microsoft Excel spreadsheet in the IFS my example program ran interactively. I recently received a message asking the following: "good stuff even though I started to use it, it has some limitations so far: doesn't work with QTEMP files. Am I right?"

I submitted my example program to batch and found that the expected spreadsheet was not generated. Looking in the job's job log I could see several messages related to files I created in QTEMP not being found. It would appear that the Java called by the GENERATE_SPREADSHEET submits a job to batch with the type BATCHI.

If I should not use files in QTEMP then I need a Standard Output file, STDOUT, in another library. I chose to create it in QGPL, but it could be in any library that is in the users' library list. As STDOUT is a source file I create it with the following:

Send email with SQL

We have been able to send email from our IBM i partitions for several releases, using IBM commands and various third party tools. I use the Send SMTP Email command, SNDSMTPEMM, that comes within the IBM i operating system. Within the latest round of Technology Refreshes, IBM i 7.5 TR3 and 7.4 TR9, comes another way, with SQL.

A new scalar function was added to the SYSTOOLS library called SEND_EMAIL. It has four parameters:

1. TO_EMAIL:  Recipients email address. Mandatory
2. SUBJECT:  Email's subject line. Mandatory
3. BODY:  Email's body. Mandatory
4. ATTACHMENT: IFS path name of the file to be sent as an attachment. Optional, if omitted no attachment is sent

For example:

Using three part name when the user profile or passwords are different

This post is to take care of an oversight that was brought to my attention. I have written several posts about using the SQL three part name, all of the examples assumed that the user name and password were the same on all of the partitions. What happens if they are not? This post will explain what to do.

For these examples I am using three partitions:

1. DEV740: This partition is running IBM i 7.4, and is the "local" partition, the one I am performing all the calls from
2. DEV730: Runs IBM i 7.3. When the connection was configured on DEV740 to DEV730 the serial number was used, therefore, DEV730 is known as G102A08R.
3. DEV720: This is the oldest partition with IBM i 7.2. My using it proves that the three part name has been around for longer than just the last few releases

I am not going to do anything too fancy for these examples. I have a file, called WHERE_AM_I, on all of these partitions. It has just one field, FLD001 that contains a unique message in each file. All I am going to do is to access these files, and show the contents on DEV740.

Capturing SQL results into a data area

The idea for this post came from a Facebook thread. The question was: "Does anyone know of a way to insert the result of an SQL SELECT into a CL Variable? I can make an SQL select into a table and read (RCVF) the file of course... But can it be done in a more "direct" way?" One of the replies to the question piqued my interest.

Before I start showing examples of code I needed a SQL statement that anyone with a recent release of IBM i could execute in their partitions. I came up with retrieving the record length for the SYSDUMMY1 table. I find the easiest way to get that information is to use the SYSFILES SQL View.

01 SELECT MAXIMUM_RECORD_LENGTH 02 FROM QSYS2.SYSFILES 03 WHERE SYSTEM_TABLE_SCHEMA = 'SYSIBM' 04 AND SYSTEM_TABLE_NAME = 'SYSDUMMY1'

Changes to the SQL View for System Values

There are times when IBM updates a SQL View to add information to it that makes more useful and easier to use than it was before. In the last round of Technology Refreshes, IBM i 7.5 TR3 and 7.4 TR9, came the addition of columns to the View that we can use to retrieve information about system values. The added rows doubled the number of columns in the View, by all means it previously had just a few rows.

The SYSTEM_VALUE_INFO View was introduced as part of IBM i 7.2 and 7.1. I have primarily used it for comparing the system values in different partitions that is an audit requirement. I could get the information from multiple partitions and display it in the same "report". The "report" is a Microsoft Excel spreadsheet.

The original version of the View contained just three columns:

1. System value name
2. Numeric value, contains system value if it is a number
3. Character value, contains systems value if it is character data

I combined the numeric and character values into one column for my "report". But I was missing one piece of information I knew would be really useful: what was the default value of the system value when the partition was created? These two are new columns in the changed View. All of the new columns are:

Calculating the difference between two dates in SQL with the result in days

I have written before about how to calculate the difference between two dates using SQL. The returned result is given in years, months, and days. But there are some occasions I need the result in days. For example I need a list of customers who have not paid in over 90 days.

Let me jump into my first example. Here I used a DDS file to contain a "date" field, like many ERP databases the date is held in a numeric field:

01 A R TESTFILER 02 A CUSTNBR 10A 03 A ENTERDTE 8P 0

To calculate how many days difference there is from the date I wrote this post, I first need to convert the field ENTERDTE from a packed numeric to a "true" date, and then I can perform the calculation using it. I am showing a very simple method of doing this. You might find this will not work in your situation. If any of the numeric fields in the file contain a numeric value that is not a valid date, zero for example, then this example would fail with an error.

Retrieving PTF cover letters using SQL

In preparation for forthcoming annual audits I was asked if there was a way to be download the PTF cover letters for all the PTFs that had been applied in 2023 in a format that could be searched?

In previous years all of the PTF cover letters were printed out and retained. If anyone had a question about whether a PTF was applied to a certain feature the printed letters were manually searched. This could take a long time.

Fortunately the last Technology Refreshes. IBM i 7.5 TR3 and 7.4 TR9, comes with a something I can use. Within them is a new Db2 for i, SQL, table function to View PTF cover letters, PTF_COVER_LETTER. If I can view a cover letter I can also insert it into a table. Which is a lot better than using the output from Display PTF Cover Letter command, DSPPTFCVR.

Using SQL to ping remote servers

Included as part of the recent Technology Refreshes, IBM i TR3 and 7.4 TR9, comes a new Db2 for i, or SQL, table function that allows me to ping a remote server and get the result in one row.

The PING table function has a number of parameters you can use with it:

1. REMOTE_SYSTEM:  This is where I would use the name of the remote server. There is a default value of *INTNETADR, which notifies the table function I am wanting to ping with the IP address.
2. REMOTE_IP_ADDRESS:  The remote server's IP address. If REMOTE_SYSTEM is not *INTNETADR then this parameter is ignored.
3. ADDRESS_VERSION_FORMAT:  Which IP address format to use. Allowed values are *IP4, *IP6, and *CALC which is the default.
4. NUMBER_OF_PACKETS_TO_SEND:  Number of packets to send. Allowed range is 1-999, default is 5.
5. PACKET_LENGTH_TO_SEND:  Length of the packet to send. Allowed range is 8 – 65500, 256 is the default.
6. WAIT_TIME:  Number of seconds to wait for the return packet. Allowed range is 1 – 120, default is 1.
7. LOCAL_IP_ADDRESS:  Local internet address that the outbound packets use. Can be an IP4 or IP6 address, or default which is *ANY.

New View for listing jobs within job queues

Included as part of the recent Technology Refreshes, IBM i TR3 and 7.4 TR9, comes a new Db2 for i, or SQL, View that will return all the jobs that are submitted to job queues.

I have written in the past about how to find a job that has been submitted to batch. This new View makes it much easier to find this information.

I have a couple of examples of the kind of information I want to find about submitted jobs. But before I talk about those I recommend that you run the following statement to see what information is returned. As there is, IMHO, a lot of useful information in the columns of this View.

Renaming IFS files using SQL

In the past if I needed to rename files in the IFS I would either use the Rename Object command, RNM, or used the 'Integrated File System' tool in ACS.

The latest round of Technology Refreshes, IBM i 7.5 TR3 and 7.4 TR9, brings us a Db2 for i, or SQL, scalar function that allows me to rename files in the IFS, IFS_RENAME. The scalar function has three parameters:

1. FROM_OBJECT:  The path of the file to be renamed.
2. TO_OBJECT:  The path of what the file will be called.
3. REPLACE:  If there is a file with the To Object name should it be replaced? 'YES' and 'NO' are the allowed values. If none is given the default is 'NO'.

SELF improvement

Having asked at several conferences I seem to be the only person using SELF to capture SQL errors. SELF, or SQL Error Logging Facility, was introduced in IBM i 7.5 TR1 and 7.4 TR7, as a way to capture SQL errors and insert them into a table that I could use to diagnose and remedy those errors. The major drawback of this tool was that I would have to list all of the SQL codes I was interested in and insert them into a SQL Global Variable every time I wanted to use SELF.

This was remedied as part of the latest Technology Refreshes, IBM i 7.5 TR3 and 7.4 TR9, now I could use the special values of '*ERROR', '*WARN', or '*ALL'. Rather than list all of the SQL codes I could just use one of these to capture all errors, all warnings, or all errors and warnings. Which makes my life a whole lot easier.

Getting statistics for jobs that have ended

One of the new additions to Db2 for i, or SQL, in the latest Technology Refreshes, IBM i 7.5 TR3 and 7.4 TR9, is a new Table function ENDED_JOB_INFO. This Table function exists in the SYSTOOLS library. ENDED_JOB_INFO allows me to retrieve some information about jobs that have, as the name suggests, ended.

ENDED_JOB_INFO has two parameters:

1. START_TIME:  The start of the range of jobs to find. If a job starts on or after this time it will be included in the results. If no value is given the default is the current timestamp less one day.
2. END_TIME:  End of the range. If no value is given the default is '9999-12-30-00.00.00.000000'.

SQL repeat scalar function

The idea for this post came from Jonathan Heinz who brought to my attention the REPEAT SQL scalar function in a comment to a post. I have to admit I had not heard of it so this post is examples of how I played with it to become familiar with its use.

Being a scalar function it can be used within a Select, Set, or Values statement. Its syntax is:

REPEAT('characters-to-repeat', number-of-times-to-repeat)

I started playing with it in ACS's Run SQL Scripts, using a Values statement:

Enumeration of constants comes to RPG

Enumeration definitions have been added to RPG as part of the Fall Technology Refreshes, IBM i 7.5 TR3 and 7.4 TR9. This allows me to define a list, or group, of constants in one definition structure. Personally I would only include related constants in one enumeration group, but I could include all of my constants, both related and unrelated, in one group.

The definition looks very similar to how to code a data structure definition.

01 dcl-enum EnumerationName ; 02 Name1 'Value 1' ; 03 Name2 'Value 2' ; 04 end-enum ;

Creating Excel spreadsheets with SQL

One of the more eye-catching additions to Db2 for i in the latest round of Technology Refreshes, IBM i 7.5 TR3 and 7.4 TR9, was a SQL scalar function that would create a Microsoft Excel compatible spreadsheet in the IFS.

For years we have been able to create Common Separated Variable length file, CSV, by copying data to the IFS. This can be opened using Microsoft Excel and then saved as an Excel compatible spreadsheet. This is the first time an easy-to-use method has been provided, as part of native IBM i, to allow us to create an Excel in the IFS from data in the Db2 database.

The new scalar function is called GENERATE_SPREADSHEET and is found in the library SYSTOOLS. It has a number of parameters that need to be passed to it:

Check if license product installed

I was performing some testing on a different IBM i partition where I wanted to take a spool file and generate a PDF in my IFS folder. I received an error saying that "Transformation services not loaded". Before I move my testing to another partition I wanted an easy way to check is "IBM Transformation Services for i" is installed.

I could check using the Work License Information, WRKLICINF, as the message suggested. But I my profile does not have sufficient authority to use it.

Fortunately there is an alternative I can use. I need to thank IBM Db2 for i chief architect, Scott Forstie, for bringing to my attention a SQL View that provides me with an easy to way to accomplish what I want.

Happy New Year 2024

Another year has passed and we all look forward into the New Year, 2024, with excitement thinking of all the good things it can bring to us all.

Before I put the old year out of mind, what did it bring us in the IBM i world?

• After seven years the end of regular support of IBM i 7.3
• Ten years after its announcement the end of service for IBM Power8 servers
• Two new Technology Refreshes for 7.4 and 7.5

What did you find the most interesting last year? These were the top ten popular posts from last year: