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#11
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tables with lots of zeroes
Since you do not have a leg to stand on bring it on. I'm sure there are
people with deeper pockets who would be more than willing to going after you for your abuse of these newsgroups. John... Visio MVP "Steve" wrote in message m... If you don't stop tracking all my posts and don't stop your public personnal attack against me you are going to be hit with am expensive lawsuit. Steve "John... Visio MVP" wrote in message ... "Steve" wrote in message m... Did you read my post first then plagarize it? Steve You are the last one who should be accusing anyone of plagarism. Are you still trying to sell a CD of all the code you gleaned from these newsgroups without giving credit to the original authors? John... |
#12
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tables with lots of zeroes
Ignore Steve.
This time he gave you about 40% of a correct answer which is better than average. Usually, when he tries to answer a question without offering to do it for you for a reasonable fee, his answer is incorrect. -- Dave Hargis, Microsoft Access MVP "buggirl" wrote: Hi everybody, I'm trying to design a table for my invertebrate data. I have many samples and over 70 taxa identified. However, most of these taxa are rare and only occur in one or two samples - therefore I end up with a table that contains many, many zeroes, (this is a common issue in ecology). In Excel, I always store my samples as ROWS and my taxa as COLUMNS. I'm looking for a more efficient way of storing this data. I want to avoid all of those zeroes!! Any suggestions? I would also like to be able to link this DATA table to a table containing taxonomic information (hierarchical classification, making it easier to group organisms as, say, 'beetles' or 'flies'). Hopefully, if I set up the DATA table correctly then the TAXONOMIC table will be a piece of cake! Thanks, buggirl |
#13
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tables with lots of zeroes
Hooray! Thank you. I have a wonderful new database that works swimmingly.
cheers, buggirl "Graham Mandeno" wrote: Hi buggirl Forget what you did in Excel! Access is NOT a spreadsheet application, it is a relational database application. It is NOT Excel on steroids. It requires a different approach from the row/column setup where every combination has a cell. Here, for a start, you need three tables: Species ------- SpcID (primary key - could be an autonumber) SpcName (text) SpcGroup (we'll talk about this later) ... any other details which relate directly to the SPECIES Samples -------- SmpID (primary key - could be an autonumber) SmpDate SmpLocation (could be text, or if the same location is sampled repeatedly then it would be better to have a foreign key to a Locations table) ... any other details which relate directly to the SAMPLE SampleCounts ------------- SampleFK (foreign key to SmpID) SpeciesFK (foreign key to SpcID) SampleCount (number) You set up a one-to-many relationship between: SmpID and SampleFK SpcID and SpeciesFK Now, if a particular species is found in a particular sample, then there will be a corresponding record in SampleCounts. If not, there will be no record. Simple! No more zeroes! For your taxonomy, it really depends on how complex you want your classification to be. The simplest would be to have one level of species grouping (beetles, flies, other insects, birds, etc). This would mean another table, SpeciesGroups, with: SpgID (PK, autonumber) SpgName (text) You then have a relationship between SpgID and SpcGroup. If you want to get into the various levels of the taxonomy, you could have several "layers" of one-to-many related tables: Kingdoms Phyla Class Order Family Genus Species However, this doesn't really work in a real taxonomy because there are all sorts of other levels which may or may not be present in a particular taxonomic chain, such as subphylum, superfamily, tribe, subspecies, and variety. Also, a "node" in the tree can often go by many names - for example, Aves/birds, or Cetoniinae/goliath beetles/flower beetles. This might seem a bit scary! If so, I'm sorry - it was not my intention - I just got a little bit carried away :-) I suggest you start first with five tables: SpeciesGroups, Species, Locations, Samples, and SampleCounts, and if you want to take the taxonomy bit further then you can add that later. -- Good Luck :-) Graham Mandeno [Access MVP] Auckland, New Zealand "buggirl" wrote in message ... Hi everybody, I'm trying to design a table for my invertebrate data. I have many samples and over 70 taxa identified. However, most of these taxa are rare and only occur in one or two samples - therefore I end up with a table that contains many, many zeroes, (this is a common issue in ecology). In Excel, I always store my samples as ROWS and my taxa as COLUMNS. I'm looking for a more efficient way of storing this data. I want to avoid all of those zeroes!! Any suggestions? I would also like to be able to link this DATA table to a table containing taxonomic information (hierarchical classification, making it easier to group organisms as, say, 'beetles' or 'flies'). Hopefully, if I set up the DATA table correctly then the TAXONOMIC table will be a piece of cake! Thanks, buggirl |
#14
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tables with lots of zeroes
That's great news! This is one database I hope won't be bug-free ;-)
Post back later if you are interested in more of the taxonomy stuff. -- Good Luck :-) Graham Mandeno [Access MVP] Auckland, New Zealand "buggirl" wrote in message ... Hooray! Thank you. I have a wonderful new database that works swimmingly. cheers, buggirl "Graham Mandeno" wrote: Hi buggirl Forget what you did in Excel! Access is NOT a spreadsheet application, it is a relational database application. It is NOT Excel on steroids. It requires a different approach from the row/column setup where every combination has a cell. Here, for a start, you need three tables: Species ------- SpcID (primary key - could be an autonumber) SpcName (text) SpcGroup (we'll talk about this later) ... any other details which relate directly to the SPECIES Samples -------- SmpID (primary key - could be an autonumber) SmpDate SmpLocation (could be text, or if the same location is sampled repeatedly then it would be better to have a foreign key to a Locations table) ... any other details which relate directly to the SAMPLE SampleCounts ------------- SampleFK (foreign key to SmpID) SpeciesFK (foreign key to SpcID) SampleCount (number) You set up a one-to-many relationship between: SmpID and SampleFK SpcID and SpeciesFK Now, if a particular species is found in a particular sample, then there will be a corresponding record in SampleCounts. If not, there will be no record. Simple! No more zeroes! For your taxonomy, it really depends on how complex you want your classification to be. The simplest would be to have one level of species grouping (beetles, flies, other insects, birds, etc). This would mean another table, SpeciesGroups, with: SpgID (PK, autonumber) SpgName (text) You then have a relationship between SpgID and SpcGroup. If you want to get into the various levels of the taxonomy, you could have several "layers" of one-to-many related tables: Kingdoms Phyla Class Order Family Genus Species However, this doesn't really work in a real taxonomy because there are all sorts of other levels which may or may not be present in a particular taxonomic chain, such as subphylum, superfamily, tribe, subspecies, and variety. Also, a "node" in the tree can often go by many names - for example, Aves/birds, or Cetoniinae/goliath beetles/flower beetles. This might seem a bit scary! If so, I'm sorry - it was not my intention - I just got a little bit carried away :-) I suggest you start first with five tables: SpeciesGroups, Species, Locations, Samples, and SampleCounts, and if you want to take the taxonomy bit further then you can add that later. -- Good Luck :-) Graham Mandeno [Access MVP] Auckland, New Zealand "buggirl" wrote in message ... Hi everybody, I'm trying to design a table for my invertebrate data. I have many samples and over 70 taxa identified. However, most of these taxa are rare and only occur in one or two samples - therefore I end up with a table that contains many, many zeroes, (this is a common issue in ecology). In Excel, I always store my samples as ROWS and my taxa as COLUMNS. I'm looking for a more efficient way of storing this data. I want to avoid all of those zeroes!! Any suggestions? I would also like to be able to link this DATA table to a table containing taxonomic information (hierarchical classification, making it easier to group organisms as, say, 'beetles' or 'flies'). Hopefully, if I set up the DATA table correctly then the TAXONOMIC table will be a piece of cake! Thanks, buggirl |
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