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Help: Query (retrieval) Navigation

This page contains information, in addition to what is described in the glossary, about navigating through the data-warehouse retrieval options.

The following topics are discussed:

• What queries are available
• Types of output
• Getting to a retrieval page
• Multi-selection help
• Miscellaneous hints (includes topics such as: expanding the viewing area of retrievals, what action to take if your session "expires" or if your retrieval does not return any data, and how to make multiple selections from a drop-down menu)

What queries are available

Queries (retrievals) are sub-divided into eight main types:

• Site information
• Constituent finder
• Ground water
• Surface water and bed sediment
• Mixed (surface- and ground water)
• Animal tissue contaminants
• Daily discharge
• Biological community samples

Each of the eight main types of queries (retrievals) allow users to select specific search criteria, as summarized below:

Table 1. Search criteria available for queries [x: is available; -: not available]

Types of output available for queries listed in the table 1

Four types of output layouts are available; see table 2 for types of output available for specific queries:

• Counts--shows the number of samples, listed by columns, for the selected criteria (wide table - 1 row per sample with parameters listed across the row)
• Serial (Simple)--parameters are listed by row (narrow table - each parameter listed on a different row)
• Basic crosstab--parameters are listed by columns (wide table - 1 row per sample with parameters listed across the row)
• Extended crosstab--parameters are listed by columns; additional columns of data are retrieved (wide table - 1 row per sample with parameters listed across the row)

An example of each type of output is shown in the "Additional explanation of data output choices" link that appears in the main frame after selecting one of the "media" types under "RETRIEVE DATA" in the left frame of the Data Warehouse home page, as described below in step1 of "Getting to a retrieval page".

Biological Community Samples (follow the "Data Retrieval Tips" link to "Biological Community: Data Retrieval Tips" for additional information)  

• Sample Count - returns the number of biological community samples collected at each station and sampling reach that is located within the geographic area specified by the sample selection criteria.
• Taxonomic List (fish and invert) - returns a list of the taxa (usually at the species level) that were present in samples collected within the geographic area specified by the sample selection criteria.
• Sample Abundance (fish and invert)-  returns the number of individuals of each taxon for each sample that were collected within the geographic area specified by sample selection criteria.

Table 2. Types of output available for the eight queries listed in table 1 [x: is available; -: not available]

Getting to a retrieval page

The "typical" sequence of navigating from the home page to a particular retrieval page is:

1. From the left frame, select one of the eight query (retrieval) types listed below RETRIEVE DATA, for example Ground Water
2. Select an output format
3. Specify values for your selected criteria
4. To perform multiple selections within a single query choice (ie state) see Multi-selection help.
5. Highlight the 'Do Not Search by xxx' to avoid conditioning your query based on that field. For example, to search for all of ARKANSAS, choose ARKANSAS under State, but set County to 'Do Not Search by County'
6. Select "Apply Parameters" at the bottom of the page

Multi-selection help----

Miscellaneous hints

• The area for viewing retrieval information can be expanded; adjust the window as needed.
• Session Expired - click on the "refresh" button on the browser menu bar (and/or open up a new browser session), then re-select your query options.
• Query asks for a password - Something overwhelmed the system in your data request. Enter password - JQPUBLIC and press Log In button.
• All search criteria that you specify must be true for data to be retrieved. For example, if you specify the following criteria for a surface water query: state={Colorado or Nebraska} and NAWQA study Unit={South Platte}, then you will retrieve data for all stream sites in Colorado or Nebraska that are part of the South Platte Study. To make the query not Study Unit specific, leave Study Unit set to 'Do Not Search by Study Unit'.
• If the search criteria has any items that are false, the results of the query will be "This worksheet doesn't contain any data". (For example, state={Iowa} and NAWQA study unit={Southern Florida}). Similarly, if both the "Enter or Select Lab Schedule Name" and "Enter or Select Parameter Name" search criteria are used, then results of the query will be "This worksheet doesn't contain any data". Be sure that either "Do not search by lab schedule" or "Do not search by parameter name" is selected from the appropriate search criterion.  Occasionally, after multiple queries have been performed using the same browser window, a data retrieval will result in the message "This worksheet doesn't contain any data". The "fix" for this situation is re-run the query after having closed all browser windows (and then opening a new browser window and re-attaching to the data warehouse.)
• Selecting multiple states, counties, site types, etc. Selecting (highlighting) multiple items from a domain list is a browser-dependent task. On Windows platforms, holding down the control key and left-mouse-button clicking allows multiple selections. On some platforms (Sun), simple clicking of items (without control key) allows multiple selections.
• Exporting data---to place the results of a query into a file on your computer, select the "export data" option at the top of the page after the query has finished tabling the data. Next, select an export format from the drop-down menu then "hit" the "export data" button (and respond to the prompts, if any, depending on the data-type that was selected). From the browser's file menu, select "Save as" and respond to the directory and filename options.
• Unrounded data - Data in the data warehouse are 'unrounded'. So, additional digits imply precision beyond the actual value of some parameters. General rules to use for interpretation of unrounded data are:
  Values rarely have more than 3 significant digits.
  The very small values are rarely below 0.001.
  Values below 0.001 should be treated as detected, but not quantified.
  

Example data retrievals

At the present time, the default is for each of the queries to retrieve a small amount of data that should return results in less than minute. If you would like to see the type of results provided by the default query, this query can be run immediately, or if you prefer, the options can be changed to other settings prior to running the query.

• How do I locate water-quality data for surface-water sites near my home?
  • Select an output format from the "Choose Query Output" drop-down menu
  • Enter or select the desired State and County options
  • Select the desired lab schedule(s) or water-quality parameters
  • Select additional search criteria as needed
  • Select "Apply Parameters" at the bottom of the page
• How do I retrieve data for multiple states? From the "Select States" option, users can select multiple states (see the "Miscellaneous hints" section above)
• How can I limit the number of parameters I retrieve? Use the "lab schedule" option, (for search criteria that include "Individual Parameters", the user can restrict retrievals to include only specified parameters)