christian singles dating indianapolis - Updating multiple columns

There are some 10,500 rows in table A, and 10,000 rows in table B. One column in table B is a foreign key to a column in table A.

Now the problem is to update the table A's three columns out of the four common columns between these two tables.

INSERT INTO Polling Places(PLACE, VCFull Addr, VCAddr, VCCity, VCZip, Phone, Alias Link) Select Vote Centers.

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I realized I could simply do one field at a time, but that doesn't seem efficient to me.

I've written the following but there's a problem with the syntax.

Therefore, it should optimize the query so that it is only accessing the row in Table B once for each row in Table A.

Question: I want to update multiple rows in my table, and I need to understand how to update multiple columns.

Answer: The landmark book "Advanced Oracle SQL Tuning The Definitive Reference" is filled with valuable information on Oracle SQL Tuning.

This book includes scripts and tools to hypercharge Oracle 11g performance and you can buy it for 30% off directly from the publisher.After each exercise, we provide the solution so you can check your answer. If you omit the WHERE clause, all records in the table will be updated!Col W ), Col Z = ( select Col Z from Table B where Col W = Table A.Col W ); Your database management system should be able to see that for each row in Table A, all three correlated sub-queries access the same row in Table B.These 3 columns in table A are to be updated based on the values present in table B's corresponding 3 columns, which has the foreign key to primary key in table A.

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