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Hi:
I need to add some records in a table called location(primary key: loc_id). What I want to do is for each location in the table, I add the same record but with a different loc_id, which can be a random string. All the other column should contain the same value. Can anyone give me a hint on how to do this in SQL server 2000 enterprise manager? thx. |
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"Hamilton sucks" <caof@mcmaster.ca> wrote in message
news:1189201676.191048.77380@22g2000hsm.googlegrou ps.com... > Hi: > I need to add some records in a table called location(primary key: > loc_id). What I want to do is for each location in the table, I add > the same record but with a different loc_id, which can be a random > string. All the other column should contain the same value. Can anyone > give me a hint on how to do this in SQL server 2000 enterprise > manager? > thx. > A strange design. If the only key is random then how do you hope to retrieve the information? If the rest of the data is to be identical then why bother copying it? DECLARE @loc_id VARCHAR(36); SET @loc_id = CAST(NEWID() AS VARCHAR(36)); INSERT INTO location (@loc_id, col1, col2, ...) SELECT col1, col2, ... FROM location ; -- David Portas |
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David Portas (REMOVE_BEFORE_REPLYING_dportas@acm.org) writes:
> "Hamilton sucks" <caof@mcmaster.ca> wrote in message > news:1189201676.191048.77380@22g2000hsm.googlegrou ps.com... >> I need to add some records in a table called location(primary key: >> loc_id). What I want to do is for each location in the table, I add >> the same record but with a different loc_id, which can be a random >> string. All the other column should contain the same value. Can anyone >> give me a hint on how to do this in SQL server 2000 enterprise >> manager? >> thx. >> > > A strange design. If the only key is random then how do you hope to > retrieve the information? If the rest of the data is to be identical > then why bother copying it? Maybe he is generating test data? > DECLARE @loc_id VARCHAR(36); > SET @loc_id = CAST(NEWID() AS VARCHAR(36)); > > INSERT INTO location (@loc_id, col1, col2, ...) > SELECT col1, col2, ... > FROM location ; That does not look like it would work out. :-) As I understand Hamilton, he wants each copied row to have each own new id. Using newid() this would be: INSERT location (loc_id, col1, col2, ...) SELECT convert(char(36), newid()), col1, col2, .... FROM location Obviously, this will not work if loc_id is shorter than 36 characters. Hamilton could use substring, but obviously the short loc_id is the bigger the possibility for duplicates. -- Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se Books Online for SQL Server 2005 at http://www.microsoft.com/technet/pro...ads/books.mspx Books Online for SQL Server 2000 at http://www.microsoft.com/sql/prodinf...ons/books.mspx |
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"Erland Sommarskog" <esquel@sommarskog.se> wrote in message
news:Xns99A56D13F4F0DYazorman@127.0.0.1... > David Portas (REMOVE_BEFORE_REPLYING_dportas@acm.org) writes: >> "Hamilton sucks" <caof@mcmaster.ca> wrote in message >> news:1189201676.191048.77380@22g2000hsm.googlegrou ps.com... >>> I need to add some records in a table called location(primary key: >>> loc_id). What I want to do is for each location in the table, I add >>> the same record but with a different loc_id, which can be a random >>> string. All the other column should contain the same value. Can anyone >>> give me a hint on how to do this in SQL server 2000 enterprise >>> manager? >>> thx. >>> >> >> A strange design. If the only key is random then how do you hope to >> retrieve the information? If the rest of the data is to be identical >> then why bother copying it? > > Maybe he is generating test data? > >> DECLARE @loc_id VARCHAR(36); >> SET @loc_id = CAST(NEWID() AS VARCHAR(36)); >> >> INSERT INTO location (@loc_id, col1, col2, ...) >> SELECT col1, col2, ... >> FROM location ; > > That does not look like it would work out. :-) > > As I understand Hamilton, he wants each copied row to have each own > new id. Using newid() this would be: > > INSERT location (loc_id, col1, col2, ...) > SELECT convert(char(36), newid()), col1, col2, .... > FROM location > > > Obviously, this will not work if loc_id is shorter than 36 characters. > Hamilton could use substring, but obviously the short loc_id is the > bigger the possibility for duplicates. > > -- > Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se > > Books Online for SQL Server 2005 at > http://www.microsoft.com/technet/pro...ads/books.mspx > Books Online for SQL Server 2000 at > http://www.microsoft.com/sql/prodinf...ons/books.mspx Thanks Erland. My mistake. -- David Portas |
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#5 |
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On Sep 7, 6:08 pm, "David Portas"
<REMOVE_BEFORE_REPLYING_dpor...@acm.org> wrote: > "Hamilton sucks" <c...@mcmaster.ca> wrote in message > > news:1189201676.191048.77380@22g2000hsm.googlegrou ps.com... > > > Hi: > > I need to add some records in a table called location(primary key: > > loc_id). What I want to do is for each location in the table, I add > > the same record but with a different loc_id, which can be a random > > string. All the other column should contain the same value. Can anyone > > give me a hint on how to do this in SQL server 2000 enterprise > > manager? > > thx. > > A strange design. If the only key is random then how do you hope to retrieve > the information? If the rest of the data is to be identical then why bother > copying it? > > DECLARE @loc_id VARCHAR(36); > SET @loc_id = CAST(NEWID() AS VARCHAR(36)); > > INSERT INTO location (@loc_id, col1, col2, ...) > SELECT col1, col2, ... > FROM location ; > > -- > David Portas Thanks, david for your . The reason for copying records is that I need to change them to new records, which are exactly the same as the old records except one column value. The loc_id is the primary key but it's not really used for searching information. So basically I don't care about the loc_id as long as they are unique, that 's why i want it to be random. |
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#6 |
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On Sep 8, 4:38 am, Erland Sommarskog <esq...@sommarskog.se> wrote:
> David Portas (REMOVE_BEFORE_REPLYING_dpor...@acm.org) writes: > > "Hamilton sucks" <c...@mcmaster.ca> wrote in message > >news:1189201676.191048.77380@22g2000hsm.googlegro ups.com... > >> I need to add some records in a table called location(primary key: > >> loc_id). What I want to do is for each location in the table, I add > >> the same record but with a different loc_id, which can be a random > >> string. All the other column should contain the same value. Can anyone > >> give me a hint on how to do this in SQL server 2000 enterprise > >> manager? > >> thx. > > > A strange design. If the only key is random then how do you hope to > > retrieve the information? If the rest of the data is to be identical > > then why bother copying it? > > Maybe he is generating test data? > > > DECLARE @loc_id VARCHAR(36); > > SET @loc_id = CAST(NEWID() AS VARCHAR(36)); > > > INSERT INTO location (@loc_id, col1, col2, ...) > > SELECT col1, col2, ... > > FROM location ; > > That does not look like it would work out. :-) > > As I understand Hamilton, he wants each copied row to have each own > new id. Using newid() this would be: > > INSERT location (loc_id, col1, col2, ...) > SELECT convert(char(36), newid()), col1, col2, .... > FROM location > > Obviously, this will not work if loc_id is shorter than 36 characters. > Hamilton could use substring, but obviously the short loc_id is the > bigger the possibility for duplicates. > > -- > Erland Sommarskog, SQL Server MVP, esq...@sommarskog.se > > Books Online for SQL Server 2005 athttp://www.microsoft.com/technet/prodtechnol/sql/2005/downloads/books... > Books Online for SQL Server 2000 athttp://www.microsoft.com/sql/prodinfo/previousversions/books.mspx Maybe I should consult about the design. The table location holds the location info about the local schools, each of them is linked to a test group and a set of students. If I want to add a new test group, which contains the same set of locations except that they are linked to the new group. Should I create a new table or add new records into tbl_location? The same problem holds for tbl_students as well since in the new group, all students' status must be reset. |
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#7 |
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"Hamilton sucks" <caof@mcmaster.ca> wrote in message
news:1189273920.752746.25660@o80g2000hse.googlegro ups.com... > > The reason for copying records is that I > need to change them to new records, which are exactly the same as the > old records except one column value. Then they are not exactly the same. Insert the new rows together including the NEW column value(s). That way you can add any relevent candidate key constraints to your table - something that wouldn't be possible if the table had to support transitional "copies" of the old data. Example: INSERT INTO tbl (col1, col2, col3) SELECT col1, @new_col2, col3 FROM tbl WHERE ... ? ; > Maybe I should consult about the design. The table location holds the > location info about the local schools, each of them is linked to a > test group and a set of students. If I want to add a new test group, > which contains the same set of locations except that they are linked > to the new group. Should I create a new table or add new records into > tbl_location? The same problem holds for tbl_students as well since in > the new group, all students' status must be reset. > This sounds very like a multi-valued or join-dependency situation. Are you familiar with the Fourth and Fifth Normal Forms? If not then look up some examples. You should satisfy yourself about the design based on your own understanding of the business rules. It's notoriously difficult to give detailed design advice in an online discussion. (Easy to spot potential problems but hard to suggest the right solutions). -- David Portas |
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