1. Sql Server Data Compare Two Tables

SQL Server provides us with different solutions to replicate or archive a database table or tables to another database, or the same database with different names. As an SQL Server Developer or Database Administrator, you may face situations when you need to check that the data in these two tables are identical, and if, by mistake, the data is not replicated between these two tables, you need to synchronize the data between the tables. Infinity best crack without box. In addition, if you receive an error message, that breaks the data synchronization or replication process, due to schema differences between the source and destination tables, you need to find an easy and fast way to identify the schema differences, ALTER the tables to make the schema identical in both sides and resume the data synchronization process. In other situations, you need an easy way to get the YES or NO answer, if the data and schema of two tables are identical or not. In this article, we will go through the different ways to compare the data and schema between two tables.

The provided methods in this article will compare tables that are hosted in different databases, which is the more complicated scenario, and can be also easily used to compare the tables located in the same database with different names. Before describing the different methods and tools that can be used to compare the tables data and schemas, we will prepare our demo environment by creating two new databases and create one table in each database, with one small data type difference between these two tables, as shown in the CREATE DATABASE and CREATE TABLE T-SQL statements below. GO Now the testing environment is ready to start describing the data and schema comparison methods.

Compare Tables Data Using a LEFT JOIN The LEFT JOIN T-SQL keyword is used to retrieve data from two tables, by returning all records from the left table and only the matched records from the right table and NULL values from the right table when there is no matching between the two tables. For data comparison purposes, the LEFT JOIN keyword can be used to compare two tables, based on the common unique column such as the ID column in our case, as in the SELECT statement below. ID The previous query will return the common five rows existing in the two tables, in addition to the row that exists in the first table and missing from the second one, by showing NULL values at the right side of the result, as shown below: You can easily derive from the previous result that, the sixth column that exists in the first table is missed from the second table. To synchronize the rows between the tables, you need to insert the new record to the second table manually. The LEFT JOIN method is helpful in verifying the new rows but will not help in the case of updating the columns values.

A SQL Server database backup and restore is a means of safeguarding and protecting data in your SQL Server databases A database snapshot is a read-only, static, transitionally consistent view of the source database. Certain features including SQL Server Reporting Services, SQL Server Analysis Services, Machine Learning Services, PolyBase, and Stretch Database are not available in SQL Server 2017 on Linux. [4] Interleaved Execution is available in all editions. Try Redgate SQL Compare - compare two SQL Server databases, synchronize the differences, automate comparisons, and manage database versioning.

Sql Server Data Compare Two Tables

If you change the Address column value of the 5th row, the LEFT JOIN method will not detect that change as shown clearly below: Compare Tables Data Using EXCEPT Clause The EXCEPT statement returns the rows from the first query (left query) that are not returned from the second query (right query). In other words, the EXCEPT statement will return the difference between two SELECT statements or tables, that helps us easily to compare the data in these tables. The EXCEPT statement can be used to compare the data in the previously created tables, by taking the difference between the SELECT * query from the first table and the SELECT * query from the second table, using the T-SQL statements below. SELECT * FROM TESTDB2. FirstComTable S The result of the previous query will be the row that is available in the first table and not available in the second one, as shown below: Using the EXCEPT statement to compare two tables is better than LEFT JOIN statement in that, the updated records will be caught in the data differences result. Assume that we updated the Address of row number 5 in the second table, and checked the difference using EXCEPT statement again, you will see that the row number 5 will be returned with the differences result as shown below: The only disadvantage of using the EXCEPT statement to compare the data in two tables is that you need to synchronize the data manually by writing an INSERT statement for the missing records in the second table.