Sorgu Tasarımı

Sorgu Tasarım Görünümü bir veritabanı sorgusu oluşturmanızı ve düzenlemenizi sağlar.

Çoğu veritabanı, bilgisayarınızdaki kayıtları süzmek ya da sıralamak için sorguları kullanır. Görünüm aynı işlevi sunucu tarafında gerçekleştirmektedir. Veritabanınız Görünümü destekleyen bir sunucuda ise, kayıtlarınızı süzerken, sonuçları görüntüleme sürenizi kısaltmak için Görünümü kullanabilirsiniz.

Selecting the Create View command from the Tables tab page of a database document, you see the View Design window that resembles the Query Design window described here.

Sorgu Tasarım pencere düzeni oluşturulan sorgu ile depolanır, fakat oluşturulan bir görünüm ile depolanamaz.

Tasarım Görünümü

Bir sorgu oluşturmak için, veritabanı belgesindeki sorgular simgesinde Sorgular'a tıklayın, ardından Tasarım Görünümünde Sorgu Oluştur'a tıklayın.

The lower pane of the Design View is where you define the query. To define a query, specify the database field names to include and the criteria for displaying the fields. To rearrange the columns in the lower pane of the Design View, drag a column header to a new location, or select the column and press +arrow key.

Sorgu Tasarım Görünümü penceresinin en üstünde, Sorgu Tasarımı Çubuğu ve Tasarım çubuğunun simgeleri görüntülenir.

Sorguyu test etmek istiyorsanız, veritabanı belgesi içindeki sorgu adı üzerinde çift tıklayın. Sorgu sonucu bir tabloda Veri Kaynağı Görünümüne benzer bir şekilde görüntülenir. Not: görüntülenen tablo geçici bir tablodur.

Sorgu Tasarımı Görünümündeki Anahtarlar

Gözat

Sorgu tasarımını ilk defa açtığınızda göreceğiniz pencerede ilk olarak sorgunuza temel olacak tabloyu veya sorguyu seçmelisiniz.

Alanları sorguya eklemek için üzerlerinde çift tıklayın. İlişkileri tanımlamak için sürükleyip bırakın.

Bir sorgu tasarlarken, seçili tablolarda değişiklik yapamazsınız.

Tabloları kaldırın

To remove the table from Design View, click the upper border of the table window and display the context menu. You can use the Delete command to remove the table from the Design View. Another option is to press the Delete key.

Tablo taşıyın ve tablo boyutunu değiştirin

Tercihlerinize göre tabloları yeniden yeniden boyutlandırabilir ve düzenleyebilirsiniz. Tabloları taşımak için, tablonun üst sınırını kullanarak tabloyu istediğiniz konuma sürükleyin. Tablonun görüntülendiği alanın boyutunu ise, fare imlecini tablo sınırına veya kenarına konumlandırın ve tablo istediğiniz boyuta gelene kadar fareyi sürükleyin.

Tablo İlişkileri

Eğer bir tablonun bir alanının isminin başka bir tablonun bir alanının ismiyle veri ilişkileri varsa bu ilişkileri sorgularınızda kullanabilirsiniz.

If, for example, you have a spreadsheet for articles identified by an article number, and a spreadsheet for customers in which you record all articles that a customer orders using the corresponding article numbers, then there is a relationship between the two "article number" data fields. If you now want to create a query that returns all articles that a customer has ordered, you must retrieve data from two spreadsheets. To do this, you must inform Collabora Office about the relationship which exists between the data in the two spreadsheets.

To do this, click a field name in a table (for example, the field name "Item-Number" from the Customer table), hold down the mouse button and then drag the field name to the field name of the other table ("Item-Number" from the Item table). When you release the mouse button, a line connecting the two fields between the two table windows appears. The corresponding condition that the content of the two field names must be identical is entered in the resulting SQL query.

Birden fazla ilişkili çalışma sayfası tabanlı bir sorgunun oluşturulması ancak Collabora Office, ilişkisel bir veritabanı için arayüz olarak kullanıldığında mümkündür.

Bir sorguda farklı veritabanlarının tablolarına erişemezsiniz. Çoklu tablolar içeren sorgular sadece bir veritabanı üzerinde oluşturulabilir.

İlişki türünü belirtmek

If you double-click on the line connecting two linked fields or call the menu command Insert - New Relation, you can specify the type of relation in the Relations dialog.

Alternatively, press Tab until the line is selected, then press Shift+F10 to display the context menu and there choose the command Edit. Some databases support only a subset of the possible join types.

İlişkileri silmek

İki tablo arasındaki ilişkiyi silmek için bağlantı çizgisine tıklayın ve ardından Delete tuşuna basın.

Alternatively, delete the respective entries in Fields involved in the Relations dialog. Or press Tab until the connecting vector is displayed highlighted, then press Shift+F10 to open the context menu and select Delete command.

Sorguyu tanımlamak

Select conditions to define the query. Each column of the design table accepts a data field for the query. The conditions in one row are linked with a Boolean AND.

Alan adlarını belirtmek

First, select all field names from the tables that you want to add to the query. You can do this either by drag-and-drop or by double-clicking a field name in the table window. With the drag-and-drop method, use the mouse to drag a field name from the table window into the lower area of the query design window. As you do this, you can decide which column in the query design window will receive the selected field. A field name can also be selected by double-clicking. It will then be added to the next free column in the query design window.

Alan adlarını silmek

To remove a field name from the query, click the column header of the field and choose the Delete command on the context menu for the column.

Sorguyu kaydetmek

Use the Save icon on the Standard toolbar to save the query. You will see a dialog that asks you to enter a name for the query. If the database supports schemas, you can also enter a schema name.

Şema

Sorguya veya tablo görünümüne atanan şemanın adını girin.

Sorgu adı ya da tablo görünümü adı

Sorgunun veya tablo görünümünün adını girin.

Verileri süzmek

Sorgu için verileri süzmek için, sorgu tasarım penceresinin alt alanında istenen ölçütleri ayarlayın. Aşağıdaki seçenekler mevcuttur:

Alan

Enter the name of the data field that is referred to in the Query. All settings made in the filter option rows refer to this field. If you activate a cell here with a mouse click you'll see an arrow button, which enables you to select a field. The "Table name.*" option selects all data fields with the effect that the specified criteria will be applied to all table fields.

Takma Ad

Specifies an alias. This alias will be listed in the query instead of the field name. This makes it possible to use user-defined column labels. For example, if the data field is named PtNo and, instead of that name, you would like to have PartNum appear in the query, enter PartNum as the alias.

Bir SQL deyiminde rumuzlar aşağıdaki gibi tanımlanır:

SELECT sütun AS alias FROM tablo.

Örneğin:

SELECT "PtNo" AS "PartNum" FROM "Parts"

Tablo

The corresponding database table of the selected data field is listed here. If you activate this cell with a mouse click, an arrow will appear which enables you to select a different table for the current query.

Sırala

If you click on this cell, you can choose a sort option: ascending, descending and unsorted. Text fields will be sorted alphabetically and numerical fields numerically. For most databases, administrators can set the sorting options at the database level.

Görünür

If you mark the Visible property for a data field, that field will be visibly displayed in the resulting query. If you are only using a data field to formulate a condition or make a calculation, you do not necessarily need to display it.

Kriterler

Veri alanının içeriğinin süzüleceği ilk ölçütü belirtir.

veya

Here you can enter one additional filter criterion for each line. Multiple criteria in a single column will be interpreted as boolean OR.

You can also use the context menu of the line headers in the lower area of the query design window to insert a filter based on a function:

İşlevler

The functions which are available here depend on those provided by the database engine.

If you are working with the embedded HSQL database, the list box in the Function row offers you the following options:

You can also enter function calls directly into the SQL statement. The syntax is:

SELECT İŞLEV(sütun) FROM tablo.

Örneğin, SQL'de bir toplamı hesaplamak için işlev çağrısı şöyledir:

SELECT SUM("Price") FROM "Article".

Except for the Group function, the above functions are called Aggregate functions. These are functions that calculate data to create summaries from the results. Additional functions that are not listed in the list box might be also possible. These depend on the specific database engine in use and on the current functionality provided by the Base driver used to connect to that database engine.

Liste kutusunda listelenmeyen işlevleri kullanmak için, işlevleri Alan altına elle girmelisiniz

You can also assign aliases to function calls. If you do not want to display the query string in the column header, enter a desired substitute name under Alias.

SQL deyimindeki karşılık gelen işlev şudur:

SELECT İŞLEV() AS alias FROM tablo

Örnek:

SELECT COUNT(*) AS count FROM "Item"

If you run such a function, you cannot insert any additional columns for the query other than as an argument in a "Group" function.

Örnekler

In the following example, a query is run through two tables: an "Item" table with the "Item_No" field and a "Suppliers" table with the "Supplier_Name" field. In addition, both tables have a common field name "Supplier_No."

The following steps are required to create a query containing all suppliers who deliver more than three items.

1. Insert the "Item" and "Suppliers" tables into the query design.

2. Link the "Supplier_No" fields of the two tables if there is not already a relation of this type.

3. Double-click on the "Item_No" field from the "Item" table. Display the Function line using the context menu and select the Count function.

4. Enter >3 as a criterion and disable the Visible field.

5. "Tedarikçiler" tablosundaki "Tedarikçi_Adı" alanına çift tıklayın ve Grup işlevini seçin.

6. Sorguyu çalıştır.

If the "price" (for the individual price of an article) and "Supplier_No" (for the supplier of the article) fields exist in the "Item" table, you can obtain the average price of the item that a supplier provides with the following query:

1. "Oge" tablosunu sorgu tasarımına ekleyin.

2. "Fiyat" ve "Tedarikçi_No" alanlarına çift tıklayın.

3. Enable the Function line and select the Average function from the "Price" field.

4. You can also enter "Average" in the line for the alias name (without quotation marks).

5. "Tedarikçi_No" alanı için Grup'u seçin.

6. Sorguyu çalıştır.

Aşağıdaki içerik menüsü komutları ve sembolleri kullanılabilir:

İşlevler

İşlev seçimi için bir satırı gösterir veya gizler.

Tablo Adı

Tablo adı için satırı gösterir veya gizler.

Rumuz İsmi

Takma isim için satırı gösterir veya gizler.

Birbirinden Farklı Değerler

Retrieves only distinct values from the query. This applies to multiple records that might contain several repeating occurrences of data in the selected fields. If the Distinct Values command is active, you should only see one record in the query (DISTINCT). Otherwise, you will see all records corresponding to the query criteria (ALL).

For example, if the name "Smith" occurs several times in your address database, you can choose the Distinct Values command to specify in the query that the name "Smith" will occur only once.

For a query involving several fields, the combination of values from all fields must be unique so that the result can be formed from a specific record. For example, you have "Smith in Chicago" once in your address book and "Smith in London" twice. With the Distinct Values command, the query will use the two fields "last name" and "city" and return the query result "Smith in Chicago" once and "Smith in London" once.

SQL'de bu komut DISTINCT yüklemine karşılık gelir.

Sınır

Bir sorgu tarafından döndürülen azami kayıt sayısını sınırlamanızı sağlar.

If a Limit construction is added, you will get at most as many rows as the number you specify. Otherwise, you will see all records corresponding to the query criteria.

Süzgeç koşullarının formüle edilmesi

When formulating filter conditions, various operators and commands are available to you. Apart from the relational operators, there are SQL-specific commands that query the content of database fields. If you use these commands in the Collabora Office syntax, Collabora Office automatically converts these into the corresponding SQL syntax via an internal parser. You can also enter the SQL command directly and bypass the internal parser. The following tables give an overview of the operators and commands:

Örnekler

Like Escape Sequence: {escape 'escape-character'}

SELECT * FROM Item WHERE ItemName LIKE 'The *%' {escape '*'}

The example will give you all of the entries where the item name begins with 'The *'. This means that you can also search for characters that would otherwise be interpreted as placeholders, such as *, ?, _, % or the period.

Outer Join Escape Sequence: {oj outer-join}

SELECT Article.* FROM {oj item LEFT OUTER JOIN orders ON item.no=orders.ANR}

Metin alanlarını sorgulama

To query the content of a text field, you must put the expression between single quotes. The distinction between uppercase and lowercase letters depends on the database in use. LIKE, by definition, is case-sensitive (though some databases don't interpret this strictly).

Veri alanlarını sorgulama

Date fields are represented as #Date# to clearly identify them as dates. Date, time and date/time constants (literals) used in conditions can be of either the SQL Escape Syntax type, or default SQL2 syntax.

SELECT {d '1999-12-31'} FROM world.years

SELECT * FROM mytable WHERE years='1999-12-31'

All date expressions (date literals) must be enclosed with single quotation marks. (Consult the reference for the particular database and connector you are using for more details.)

Evet/Hayır alanlarını sorgulama

Evet/Hayır alanlarını sorgulamak için, dBASE tabloları için aşağıdaki söz dizimini kullanın:

The syntax depends on the database system used. You should also note that Yes/No fields can be defined differently (only 2 states instead of 3).

Parametre sorguları

Parameter queries allow the user to input values at run-time. These values are used within the criteria for selecting the records to be displayed. Each such value has a parameter name associated with it, which is used to prompt the user when the query is run.

Parameter names are preceded by a colon in both the Design and SQL views of a query. This can be used wherever a value can appear. If the same value is to appear more than once in the query, the same parameter name is used.

In the simplest case, where the user enters a value which is matched for equality, the parameter name with its preceding colon is simply entered in the Criterion row. In SQL mode this should be typed as WHERE "Field" = :Parameter_name

Parameter names may not contain any of the characters <space>`!"$%^*()+={}[]@'~#<>?/,. They may not be the same as field names or SQL reserved words. They may be the same as aliases.

A useful construction for selecting records based on parts of a text field's content is to add a hidden column with "LIKE '%' || :Part_of_field || '%'" as the criterion. This will select records with an exact match. If a case-insensitive test is wanted, one solution is to use LOWER (Field_Name) as the field and LIKE LOWER ( '%' || :Part_of_field || '%' ) as the criterion. Note that the spaces in the criterion are important; if they are left out the SQL parser interprets the entire criterion as a string to be matched. In SQL mode this should be typed as LOWER ( "Field_Name" ) LIKE LOWER ( '%' || :Part_of_field || '%' ).

Parameter queries may be used as the data source for subforms, to allow the user to restrict the displayed records.

Parametre Girişi

The Parameter Input dialog asks the user to enter the parameter values. Enter a value for each query parameter and confirm by clicking OK or typing Enter.

The values entered by the user may consist of any characters which are allowable for the SQL for the relevant criterion; this may depend on the underlying database system.

The user can use the SQL wild-card characters "%" (arbitrary string) or "_" (arbitrary single character) as part of the value to retrieve records with more complex criteria.

SQL Kipi

SQL stands for "Structured Query Language" and describes instructions for updating and administering relational databases.

In Collabora Office you do not need any knowledge of SQL for most queries, since you do not have to enter the SQL code. If you create a query in the query designer, Collabora Office automatically converts your instructions into the corresponding SQL syntax. If, with the help of the Switch Design View On/Off button, you change to the SQL view, you can see the SQL commands for a query that has already been created.

You can formulate your query directly in SQL code. Note, however, that the special syntax is dependent upon the database system that you use.

If you enter the SQL code manually, you can create SQL-specific queries that are not supported by the graphical interface in the Query designer. These queries must be executed in native SQL mode.

By clicking the Run SQL command directly icon in the SQL view, you can formulate a query that is not processed by Collabora Office and sent directly to the database engine.