So, I am returning rows 21 through 26 for the sake of clarity in the result set. That the first ten rows in the AdventureWorks2014 database will have the same cityĪnd postal code even though they have different "AddressID’s". Note: Instead of doing a simple SELECT statement to view the results, I’mĪdding an OFFSET / FETCH option to return a different set of data. PostalCode or only in certain cities this would be specified in the WHERE Wanted to update the tuples in the Test.Person table that have a certain This will allow for updating onlyĬertain rows while leaving the other rows untouched. We could take it a step further by adding a WHERE clause to filter out anyĬolumns from the referenced or updated tables. JOIN by using the matching BusinessEntityID and AddressID columns respectively from Finally, we linked the source and target tables via an INNER Updated and set them to equal the values found in the source table, matching theĬolumns by aliases. With the SET keyword, we specified which columns in the target table we want Link is the "BusinessEntityID" column and the "AddressID" Relationship, although the keys are not necessary. Both columns will have related (corresponding) dataĪnd compatible datatypes and often those columns will have a primary / foreign key The INNER JOIN clause links two or more tables by a relationship between twoĬolumns, one on each table. AddressID GO Explaining how the INNER JOIN option works Person (BusinessEntityID ) GO INSERT INTO Test. PersonAddress ADD CONSTRAINT FK_PersonAddress_AddressID FOREIGN KEY (AddressID ) REFERENCES Test. PersonAddress (īusinessEntityID INT, AddressID INT, City NVARCHAR (30 ), PostalCode NVARCHAR (15 ) ) GOĪLTER TABLE Test. Person ADD CONSTRAINT PK_Person_BusinessEntityID PRIMARY KEY CLUSTERED (BusinessEntityID ) GO INSERT INTO Test. Person (īusinessEntityID INT NOT NULL, FirstName NVARCHAR (50 ), LastName NVARCHAR (50 ), City NVARCHAR (30 ), PostalCode NVARCHAR (15 ) ) GOĪLTER TABLE Test. USE AdventureWorks2014 GO CREATE SCHEMA Test AUTHORIZATION dbo GO CREATE TABLE Test. Us to work with and manipulate the data without disturbing any tables that pre-exist Person.Address tables provided in the Adventurworks2014 database. We will also create a primary – foreign key constraint to link the two tables.įinally, we will populate the tables with data from the existing Person.Person and Two tables, "Test.Person" and "Test.PersonAddress". In the following query, we will create a schema named "Test" and Once it’s downloaded, simply follow the basic steps to restore from a If you do not have the AdventureWorks2014 database installed already, you can Afterwards, we will simply dump both tables as well as the schema. We will, however, create a couple of new tables along with a new schema to work Installed, don’t worry, we will not be changing any of the tables or data. Working with the AdventureWorks2014 database. Getting a Test Databaseįor simplicity's sake and for keeping with a standard test database, we will be In my sample, I am using a test database named Use a Test SystemĪlways use a test server and a test database for testing and learning. You cannot put a VARCHAR value in an INT field. Updating are of the same or compatible datatypes as the source columns. Remember, you will need to make sure that the columns you are Second option we will use the MERGE statement and finally, we will use a nested The first option, we will use the JOIN as a form of a SELECT statement and in the In one or more columns with unique values that are stored in a separate table. I guess/hope there is a simplier and more maintainable way to do that.In this tutorial, we will explore three options that will update all the tuples "Table1_id = (SELECT max(Table1_id) FROM Table1)", sourceRecord_idx, sourceRecord_idx, sourceRecord_idx) Īs you can see for each single field I must write its specific SET case and moreover the value for each filed is retrieved by a select. "fiedl3 = case when fiedl3 is null then (SELECT fiedl3 FROM Table1 WHERE Table1_id = %d) else fiedl3 end "\ "fiedl2 = case when fiedl2 is null then (SELECT fiedl2 FROM Table1 WHERE Table1_id = %d) else fiedl2 end, "\ "fiedl1 = case when fiedl1 is null then (SELECT fiedl1 FROM Table1 WHERE Table1_id = %d) else fiedl1 end, "\ I was wandering if it's possible to write a sql query that take a whole record from a table and update all NULL fields in another record of the same table. Moreover my code is very very unmanageable, because of if in the future the table structure will change I'll must rewrite the query to add or remove fields. I Got it working but I'm wondering if my solution is correct or something is missing and if I could write it in a more compact and speeder way. What I'm doing is to UPDATE the last inserted row of a table with data from another record af the same table, or from another similar table. I have a sqlite3 DB with a different tables.
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