Queries are working on the following database. Example 4 : List the names of each class in the way of being seen once in the student table. Example 5: List the students with Female gender and the class 10Math in the student table. Example 6: List the names, surnames and classes of the students in the class 10Math or 10Sci in the student table.
Example 7: List the students name surname and school number in the student table. Example 8: List the students name and surname by combining them as name surname in the student table. If each table has a Customer ID field, which forms the basis of a one-to-many relationship between the two tables. You can create a query that returns orders for customers in a particular city, for example, Las Vegas, by using the following procedure:. Open the database. On the Create tab, in the Query group, click Query Design.
On the Tables tab, double-click Customers and Orders. This line shows the relationship between the two tables. In the Customers table, double-click Company and City to add these fields to the query design grid. In the query design grid, in the City column, clear the check box in the Show row. In the Criteria row of the City column, type Las Vegas. Clearing the Show check box prevents the query from displaying the city in its results, and typing Las Vegas in the Criteria row specifies that you want to see only records where the value of the City field is Las Vegas.
In this case, the query returns only the customers that are located in Las Vegas. In the Orders table, double-click Order ID and Order Date to add these fields to the next two columns of the query design grid. On the Design tab, in the Results group, click Run. The query runs, and then displays a list of orders for customers in Las Vegas. If you frequently want to run variations of a particular query, consider using a parameter query.
When you run a parameter query, the query prompts you for field values, and then uses the values that you supply to create criteria for your query. Note: You cannot create a parameter query in an Access web app. Continuing from the previous example where you learnt to create a select query that returns orders for customers located in Las Vegas, you can modify the select query to prompt you to specify the city each time that you run the query.
To follow along, open the database that you created in the previous example:. In the Navigation Pane, right-click the query named Orders by City that you created in the previous section , and then click Design View on the shortcut menu. In the query design grid, in the Criteria row of the City column, delete Las Vegas , and then type [For what city? The string [For what city? The square brackets indicate that you want the query to ask for input, and the text in this case, For what city?
Note: Neither a period. Select the check box in the Show row of the City column, so that the query results will display the city. The query prompts you to enter a value for City. What if you don't know what values you can specify? You can use wildcard characters as part of the prompt:. In the query design grid, in the Criteria row of the City column, type Like [For what city? You can also specify what type of data a parameter should accept.
When you specify the data type that a parameter should accept, users see a more helpful error message if they enter the wrong type of data, such as entering text when currency is expected. If a parameter is set to accept text data, any input is interpreted as text, and no error message is displayed. In the Query Parameters dialog box, in the Parameter column, type the prompt for each parameter for which you want to specify the data type. Make sure that each parameter matches the prompt that you use in the Criteria row of the query design grid.
For more information, see using parameters to ask for input when running a query. The Total row in a datasheet is very useful, but for more complex questions, you use a totals query.
A totals query is a select query that allows you to group and summarize data, like when you want to see total sales per product. In a totals query, you can use the Sum function an aggregate function , to see total sales per product. Note: You cannot use aggregate functions in an Access web app.
Use the following procedure to modify the Product Subtotals query that you created in the previous example so that it summarizes product subtotals by product. Note: Although they have similar names, the Totals row in the design grid and the Total row in a datasheet are not the same:.
When you use the Totals row in the design grid, you must choose an aggregate function for each field. If you do not want to perform a calculation on a field, you can group by the field.
There is syntax highlighting to make code easier to navigate and an autocomplete function to speed up code production. To further support navigation there is an auto lookup feature so that when the user types a query a list of columns with tables will come up for the user to click on. The price of the software depends on the number of users you want to support.
All Supported Databases. You can also download Query Xtractor for free. When you are typing, you can benefit from contextual recommendations that suggest elements such as tables, functions, and columns you could use. Auto Formatting and syntax coloring make it easy to find your way around code and manage SQL files of all sizes. The user can create code and view real-time feedback on issues and fixes to improve their code.
Similarly, there is a SQL Debugger that locates coding errors so that you can debug them. However, if you want to view the price for Idera Rapid SQL you will have to contact the sales team directly.
While some can be used to build queries from scratch others simply highlight poorly performing queries. Finding a tool that fits most closely with your use case will deliver the best results. A unique identifier is a numeric field in a database table. It is populated by a sequence that ensures that each record has a unique value in that field. Foreign keys in other tables should reference the unique identifier column in order to get accurate joins to records in the target table.
In its original form, SQL is not a programming language, as is explained by its full name, it is a query language. There are four types of schemas in databases. So, the task of creating a schema is different, depending on which type of schema you have been asked to create.
The diagram that shows the plan of all of the objects that will go into a database is called a schema. You create that with a drawing tool — this is the Logical Schema. The space that contains all of those objects is also called a schema — this is an industry term that describes the workspace that holds a database. Different DBMSs offer different methods to create that type of schema.
The mapping between the database and the physical storage is called the Physical Schema and that is usually generated by the DBMS when it sets up a schema for holding tables. The mapping between a front-end that gives access to the database to users and how that relies on the logical objects in the database is called the View Schema. That is usually created by a systems analyst as part of the spec to pass to a programmer.
The non-database reports can be delivered in your preferred format. Groupings created within the query results grid are retained within the export, including grouping in Microsoft Excel. The SQL editor enables you to connect to different databases, integrate, virtualize and export your data over web services when used in combination with Invantive Web Service. The SQL editor enables you to upload queries, open recent and historical files, edit and execute your scripts with ease.
The parser allows you to highlight SQL syntax, validate, clean up, and parse your text based scripts with ease. With the SQL Parser and editor you will be able to check scripts before they run, build and apply complex queries to your data warehouse easily.
With the Graphical User Interface GUI you will be empowered to simple integrate data, execute queries and manage multiple databases.
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