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pluginto:useful_sql_queries [2026/01/21 17:16] – joetulenkopluginto:useful_sql_queries [2026/01/21 17:21] (current) – joetulenko
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 9. LEFT JOIN - let's say I want info on a bunch of samples from multiple fields/tables in ICE-D but some samples may not have all of the information in every field in my query. Using a standard JOIN, samples that are missing info from one or more of my selected fields may not be included in my results list. However, using a LEFT JOIN you can select samples that match the filtering criteria and have information filled in for at least one of the selected fields in my query. 9. LEFT JOIN - let's say I want info on a bunch of samples from multiple fields/tables in ICE-D but some samples may not have all of the information in every field in my query. Using a standard JOIN, samples that are missing info from one or more of my selected fields may not be included in my results list. However, using a LEFT JOIN you can select samples that match the filtering criteria and have information filled in for at least one of the selected fields in my query.
  
-In the example below, I am searching for sample names, sample 10Be concentrations, and sample 14C concentrations for alpine glacier samples across the Western United States. Using a LEFT JOIN, I will select samples that satisfy one of the following criteria:+In the example below, I am searching for sample names, sample 10Be (and/or 26Al) concentrations, and sample 14C concentrations for alpine glacier samples across the Western United States. **//Using a LEFT JOIN, I will select samples that satisfy one of the following criteria://**
  
-(1) samples that only have 10Be concentrations (or 26Al concentrations) \\+(1) samples that only have 10Be concentrations (and/or 26Al concentrations) \\
 (2) samples that only have 14C concentrations \\ (2) samples that only have 14C concentrations \\
 (3) samples that have both 10Be (and/or 26Al concentrations) AND 14C concentrations \\ (3) samples that have both 10Be (and/or 26Al concentrations) AND 14C concentrations \\
-(4) rare case where samples have none of the above - likely because a sample is linked to an incomplete entry in either the 10Be/26Al table or the 14C table that's missing nuclide concentration(s) \\+(4) samples have none of the above - likely because a sample is linked to an incomplete entry in either the 10Be/26Al table and/or the 14C table that's missing nuclide concentration(s) \\
  
-(using a standard JOIN would only select samples that satisfy criteria 3)+(using a standard JOIN would only select samples that satisfy criteria 3 and in rare cases 4)
  
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