ExecuteSQL, Level: Intermediate, Version: FM 13 or later

Fast Summaries Revisited

Update 30 May 2018: see also Fast Summaries Re-revisited.

If you do complex data analysis, then from time to time you probably need to group, summarize, and parse data into variables and/or fields. There are various ways to accomplish this, including the Fast Summary technique, which regular readers of this blog may be familiar with, as it has made a number of appearances here over the years.

Well today we’re going to look at a couple alternatives to Fast Summaries, with the help of some demo files, which you can use to do your own benchmarking.

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Or, if you’d rather not do your own benchmarking, scroll down to see results from my tests. Bottom line: each of these three techniques can be fastest, depending on circumstances.

(Also, if you’ve been putting off exploring Perform Script On Server, a.k.a. PSOS, host the demo files on FileMaker Server 13 or later. The reporting routine optionally uses PSOS, so you can dive in painlessly and see what you’ve been missing.) Continue reading “Fast Summaries Revisited”

ExecuteSQL, Level: Intermediate, SQL, Version: FM 12 or later

Outer Joins in FileMaker 12, part 3

I’ve said before, and no doubt will say again, that one of my favorite things about this blog is how much I learn from your feedback and the demo files you send me.

Recently I received a file from Otmar Kramnis of the Hochschule Luzern demonstrating the fastest SQL-based method I have yet seen to solve the challenge we looked at in part 1 and in part 2, and with a few minor modifications, this is the demo we’re going to focus on today:  Outer Join Demo 7

As you may recall, the aim is to show a week’s worth of daily sales totals for all employees whether they had any sales or not.

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Or, to restate the problem in more generic terms: we need to show all values from table A, whether or not there are any matching values in table B. This is known as an “outer join”, or more precisely a “left outer join”, since we want to see all values in the “left” table (Employees), whether or not they have corresponding matches in the “right” table (Sales).

Continue reading “Outer Joins in FileMaker 12, part 3”

Beverly Voth, ExecuteSQL, Level: Intermediate, SQL, Version: FM 12 or later

PDF version of FM 12 ExecuteSQL Reference

Beverly Voth has produced a PDF version of The Missing SQL Reference with some additional material not available in her original posting from October 19th.

And the SQL4_fmdev2.fmp12 demo file has been updated with new queries.

Thank you Beverly for this major contribution to the FileMaker community.

ExecuteSQL, Level: Intermediate, Version: FM 12 or later

Outer Joins in FileMaker 12, part 2

Last week in part 1 we looked at four “outer join” reporting approaches. Two of them involved ExecuteSQL, and I ended that section with the plea: Of course it’s possible that you, dear reader, know some FileMaker SQL voodoo to speed things up, and would be willing to share? Well Dr. Osamu Noda of Japan was kind enough to not only respond, but has provided a pair of demos (Outer Join Demo 5 and Outer Join Demo 6) which are significantly faster and which I am sharing with his permission.

Both of the demos are based on my original files from last week, and as you may recall, the aim was to show a week’s worth of sales for all employees whether they had any sales or not.

Continue reading “Outer Joins in FileMaker 12, part 2”

ExecuteSQL, Level: Intermediate, SQL, Version: FM 12 or later

Outer Joins in FileMaker 12, part 1

Recently I had an on-screen reporting challenge, and decided to try several different approaches to see which would be fastest. The challenge: Starting with two tables, one containing 20 Employees, and one containing 2,000 Sales records for the current year…

…display daily sales totals per employee in a seven-day grid, like so:

Continue reading “Outer Joins in FileMaker 12, part 1”

ExecuteSQL, Level: Intermediate, SQL, Version: FM 10 or later

Dwindling Value Lists, part 1

A few months ago I mentioned “dwindling value lists” in passing, and said I would do a proper article on them at some point in the future. Well, then FM 12 was released and I went on an ExecuteSQL binge, so I’m just now getting around to honoring my promise.

Dwindling Value Lists (DVLs) are value lists that shrink up, by removing individual list items as they are selected. They can come in very handy when you need to schedule resources and want to prevent double booking. This example comes from one of today’s demo files, Dwindling Value Lists, and shows how a DVL might be used to schedule employees for a work shift.

Essentially, a DVL is a filtered value list that updates in real time (or something very close to real time), and this is done by building a multiline key of selected values, and then filtering the VL to only show remaining eligible values. Continue reading “Dwindling Value Lists, part 1”

ExecuteSQL, Level: Intermediate, SQL, Version: FM 12 or later

FM 12 ExecuteSQL: Robust Coding, part 2

In part 1, I listed six scenarios that could potentially cause ExecuteSQL code to break:

…and managed to get through the first five before running out of steam. This time, we’re going to examine #6 on the list, and then look at a few miscellaneous odds ’n’ ends, and today’s demo file is ExecuteSQL Sandbox, v2, if you’d like to follow along.

Changing a Field Type

Why would changing a field’s type cause a problem? Well, first off, as I mentioned last month, if you are using that particular field as a predicate in a JOIN, the query will break, and your reward will be the the dreaded “?”.

I don’t have a fix for this, just some advice: Don’t change a field’s type if you’ve used it as a JOIN predicate in a working SQL statement. (The only reason I’ve needed to change a field type recently was to fix a broken JOIN where the field types were mismatched.)

Continue reading “FM 12 ExecuteSQL: Robust Coding, part 2”

ExecuteSQL, Level: Intermediate, SQL, Version: FM 12 or later

FM 12 ExecuteSQL: Robust Coding, part 1

[Note: Some of the material in this article, and in today’s demo file ExecuteSQL Sandbox, previously appeared in my March 2011 article, Custom Functions for Internal SQL.]

The other day a colleague remarked, “You know, it’s going to be interesting to see if you SQL guys are still so excited about ExecuteSQL when something gets renamed and your code breaks.” He had a good point: code is “brittle” if it works initially, but then subsequently breaks as a result of a seemingly innocuous action.

Here are some things that can cause ExecuteSQL code to break:

  1. Renaming a table occurrence (TO)
  2. Renaming a field
  3. Using a “reserved word” as a field or TO name
  4. Having a problematic character in a field or TO name
  5. Executing the code in a foreign country (!)
  6. Changing a field’s type (e.g., from text to number or vice versa)

…and today we’re going to look at some defensive measures we can employ to prevent problems when these things occur.

Using the “orders” table in the demo file

Continue reading “FM 12 ExecuteSQL: Robust Coding, part 1”

ExecuteSQL, Level: Intermediate, SQL, Version: FM 12 or later

FM 12 ExecuteSQL: Dynamic Parameters, pt 2

This is a quick follow-up to part 1, with a couple more observations about dynamic parameters.

Embedded Apostrophes

Here’s one I can’t believe I forgot to mention the other day:  A major ExecuteSQL headache that dynamic parameters can alleviate is the dreaded “embedded apostrophe” problem. In case you aren’t familiar with it, if your text string contains an embedded apostrophe, in standard SQL you must escape it by prepending another apostrophe, for example compare these two “standard” (non-dynamic) queries:

As you might expect, you don’t have to worry about this if you instead use a dynamic parameter… just quote the search term the way you would any FileMaker text string (i.e., in double quotes) and go about your business.

Continue reading “FM 12 ExecuteSQL: Dynamic Parameters, pt 2”

ExecuteSQL, Level: Intermediate, SQL, Version: FM 12 or later

FM 12 ExecuteSQL: Dynamic Parameters, pt 1

I have a confession: when I first read about dynamic parameters in the Help entry for ExecuteSQL, my initial reaction was, “Why do they have to make it so darn complicated?”

I have another confession: I am now singing a very different tune. I’ll get to the reason for this in a minute, but first let’s compare two ExecuteSQL statements, which were discussed last month in FM 12 ExecuteSQL, part 1.

Continue reading “FM 12 ExecuteSQL: Dynamic Parameters, pt 1”