ODBC  (PRIMARY KEY)

I want to create a table, SQL statement is:
CREATE TABLE voc
e CHAR(25) NOT NULL PRIMARY KEY,
r CHAR(70)
SQL exception is:
[Microsoft][ODBC Paradox Driver] This property is not supported for external dat
a sources or for databases created with a previous version of Microsoft Jet.
If I use the same statement without 'NOT NULL' it says:
[Microsoft][ODBC Paradox Driver] 'Index_7752BE35_A919_49DD' is not a valid name.
Make sure that it does not include invalid characters or punctuation and that
it is not too long.
Where is the problem?

Format of create table if you were to use optional constraints:
create table "tablename"
("column1" "data type"
[constraint],
"column2" "data type"
[constraint],
"column3" "data type"
[constraint]);
[ ] = optional
What are constraints? When tables are created, it is common for one or more columns to have constraints associated with them. A constraint is basically a rule associated with a column that the data entered into that column must follow. For example, a "unique" constraint specifies that no two records can have the same value in a particular column. They must all be unique. The other two most popular constraints are "not null" which specifies that a column can't be left blank, and "primary key".

Similar Messages

  • Determining the primary key in a database table

    Hi people..
    I am building an interface which displays the database information...according to the specified datasource name..
    Up till now i managed to display the different tables and the respective attributes...
    Is there a way of how i can determine (through java code) if an attribute is the primary key or not of the corresponding table??
    Thanks for your time..
    Regards
    S

    Hi thanks for your reply however when i run the above code i get the following exception..
    java.sql.SQLException: [Microsoft][ODBC Driver Manager] Driver does not support this function
    the statement causing such exception is ..
    ResultSet rs = dbMetaData.getPrimaryKeys(null, null, tableName);
    Do you have any suggestions...??? Sincerely i dont know what i can do..If it can helps the database i m connecting to is an access 2000 database and i am connecting to the database like this:
    Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
    Connection connection = DriverManager.getConnection("jdbc:odbc:"+dataSourceName,username,password);
    Thanks a lot again

  • Auto Increment Primary Keys

    I am trying to migrate from SQL Server. I want to setup tables which generate sequencial Primary keys on adding records to the table. I have a VB application which is using ADO with an ODBC connection. How does one use the Oracle Enterprise Console Manager to set a Primary Key to increment on the adding of new records automatically. In SQL Server one just needs to set an Identity, Identity Seed and Identitiy Increment. In Access there is a datatype called AutoNumber. Help would be greatly appreciated. I am using 9i with a standalone Enterprise Console Manager. Thanks in Advance.

    You first have to create a sequence and then the trigger below:
    Instead of data in single quotes(') you must specify the appropriate for your db names
    CREATE OR REPLACE TRIGGER 'Schema'.'trigger_name' BEFORE
    INSERT ON 'table_name'
    FOR EACH ROW
    BEGIN
    SELECT 'sequence_name'.nextval into :new.'column_name' from dual;
    END
    ;

  • How can I use a mySQL database schema with numeric auto increment primary key instead of GUID?

    Hello!
    I'm using the TestStand "MySQL Insert (NI)" database schema with GUID as primary key. So everything works fine.
    But I prever using numeric values as primary key, because the database is in conjunction with another database which uses numeric values as primary key.
    Is this possible?
    Has anyone an idea how I can modify the "Generic Recordset (NI)" for use with MySQL?
    Thanks!
    Configuration:
    Microsoft Windows XP
    TestStand 3.1
    MySQL 4.1.12a
    MySQL ODBC 3.51 Driver
    Brosig

    Adam -
    The TestStand Database Logging feature does not allow you to run a separate SQL command after executing the command for a statement(table), so I do not think that you can use an auto incrementing column for the tables. There is just no way to get it back in a generic way. One option that I tried is something similar to the Oracle schema where you call a store procedure to return a sequence ID for each record that you want to add.
    So you would have to create the following sequence table in MySQL:
    CREATE TABLE sequence (id INT NOT NULL);
    INSERT INTO sequence VALUES (0);
    Then create a stored procedure as shown below that will increment the sequence value and return it in a recordset:
    CREATE PROCEDURE `getseqid`()
    BEGIN
            UPDATE sequence SET id=LAST_INSERT_ID(id+1);
            SELECT LAST_INSERT_ID();
    END
    Then update the MySQL tables to use INT primary and foreign key values, so the TestStand MySQL SQL file to create all tables would have text like this:
    CREATE TABLE UUT_RESULT
     ID    INT  PRIMARY KEY,
    ~
    CREATE TABLE STEP_RESULT
     ID    INT  PRIMARY KEY,
     UUT_RESULT   INT  NOT NULL,
    ~
    Then update the schema primary and foreign key columns in the TestStand Database Options dialog box to be INT to match the table. For the primary key columns, you will have to set the Primary Key Type to "Get Value from Recordset" and set the Primary Key Command Text to "call getseqid()". This will call the stored procedure to determine the next value to use as the ID value.
    Hope this helps...
    Scott Richardson
    National Instruments

  • Primary keys on incorrect fields

    Hi. I am migrating a backend Access 97 database to Oracle 8.1.6.
    I have migrated the structure, but not data. I have noticed now that if I attach the new oracle tables to Access, even to a blank database, Access reports wrong columns as being the primary key. Yet, when I look at the entries for the primary keys in all_cons_columns they appear to be correct. Does anyone know how this would happen?
    Thanks,
    Ann Cantelow

    I have tried both the ODBC driver from the oracle client software, and the latest MDAC ODBC driver that Microsoft provides. The problem remains the same for each.
    These incorrect primary keys are on tables that have unique indexes- the attached table shows the first unique index as being the primary key. Remove all unique indexes, and the primary key is found correctly.
    Thanks,
    Ann Cantelow

  • How to create one primary key for each vendor

    Hi all
    i am doing IDOC to jdbc scenario
    i am triggering idoc from R/3 and the data is going into DB table vendor through XI.
    structures are as follows:
    sender side: ZVendorIdoc (this is a customized IDOC , if i triger IDOC for multiple vendors then it triggers only 1 idoc with multiple segment )
    Receiver side:
    DT_testVendor
        Table
            tblVendor
                action UPDATE_INSERT
                access                     1:unbounded
                    cVendorName         1
                    cVendorCode        1
                    fromdate                1
                    todate                    1
                 Key1
                    cVendorName         1
    if i trigger idoc for multiple vendors ,for example vendor 2005,2006 and 2010 . then i can see that the only key comes from the very first field (2005) and the whole record for vendor 2005,2006 and 2010  goes into the table with this(2005) as a primary key
    now again if i send data for these three vendor 2005, 2006 , 2010, in which record for the vendor 2005 is same and for 2006 and 2010 are different than it takes 2005 as a primary key and it does not update the data in the table.
    my requirement is like this:   for each vendor there should be one unique key assigned.
                                              for above said example there should come three keys one for each vendor .
    could you please help me how to do this???????????

    Hi,
      In Mapping Make the statement is 0-unbounded.For each vendor create a statement.This will solve your problem.
    Regards,
    Prakasu.M

  • Error While Deploying A CMP Entity Bean With A Composite Primary Key

    Hello all,
    I have a problem deploying CMP Entity beans with composite primary keys. I have a CMP Entity Bean, which contains a composite primary key composed of two local stubs. If you know more about this please respond to my post on the EJB forum (subject: CMP Bean Local Stub as a Field of a Primary Key Class).
    In the mean time, can you please tell me what following error message means and how to resolve it? From what I understand it might be a problem with Sun ONE AS 7, but I would like to make sure it's not me doing something wrong.
    [05/Jan/2005:12:49:03] WARNING ( 1896):      Validation error in bean CustomerSubscription: The type of non-static field customer of the key class
    test.subscription.CustomerSubscriptionCMP_1530383317_JDOState$Oid must be primitive or must implement java.io.Serializable.
         Update the type of the key class field.
         Warning: All primary key columns in primary table CustomerSubscription of the bean corresponding to the generated class test.subscription.CustomerSubscriptionCMP_1530383317_JDOState must be mapped to key fields.
         Map the following primary key columns to key fields: CustomerSubscription.CustomerEmail,CustomerSubscription.SubscriptionType. If you already have fields mapped to these columns, verify that they are key fields.Is it enough that a primary key class be serializable or all fields have to implement Serializable or be a primitive?
    Please let me know if you need more information to answer my question.
    Thanks.
    Nikola

    Hi Nikola,
    There are several problems with your CMP bean.
    1. Fields of a Primary Key Class must be a subset of CMP fields, so yes, they must be either a primitive or a Serializable type.
    2. Sun Application Server does not support Primary Key fields of an arbitrary Serializable type (i.e. those that will be stored
    as BLOB in the database), but only primitives, Java wrappers, String, and Date/Time types.
    Do you try to use stubs instead of relationships or for some other reason?
    If it's the former - look at the CMR fields.
    If it's the latter, I suggest to store these fields as regular CMP fields and use some other value as the PK. If you prefer that
    the CMP container generates the PK values, use the Unknown
    PrimaryKey feature.
    Regards,
    -marina

  • Logical standby and Primary keys

    Hi All,
    Why primary keys are essential for creating logical standby database? I have created a logical standby database on testing basis without having primary keys on most of the tables and it's working fine. I have not event put my main DB in force logging mode.

    I have not event put my main DB in force logging mode. This is because, redo log files or standby redo logfiles transforms into set of sql statements to update logical standby.
    Have you done any DML operations with nologging options and do you notice any errors in the alert.log? I just curious to know.
    But I wanted to know that, while system tablespace in hot backup mode,In the absence of both a primary key and a nonnull unique constraint/index, all columns of bounded size are logged as part of the UPDATE statement to identify the modified row. In other words, all columns except those with the following types are logged: LONG, LOB, LONG RAW, object type, and collections.
    Jaffar

  • Query to return list of all missing primary key ids from table T1

    I found this query online that returns a start and stop for a range of all missing primary key id values from table T1. However i want to rewrite this query to return a whole list of all the missing primary key ids and not a start and stop range. any help plz?
    select strt, stp
    from (select m.id + 1 as strt,
    (select min(id) - 1 from T1 x where x.id > m.id) as stp
    from T1 m left outer join T1 r on m.id = r.id - 1 where r.id is null)x where stp is not null

    with t as
              select  1 as id from dual union all
              select  2 as id from dual union all
              select  3 as id from dual union all
              select  5 as id from dual union all
              select  8 as id from dual union all
              select 10 as id from dual union all
              select 11 as id from dual union all
              select 20 as id from dual
    select  id_start + level missing_id
      from  (
             select  id id_start,
                     nullif(lead(id) over(order by id) - 1, id) id_end
               from  t
      start with id_end is not null
      connect by prior id_start = id_start
             and prior dbms_random.random is not null
             and level <= id_end - id_start
    MISSING_ID
             4
             6
             7
             9
            12
            13
            14
            15
            16
            17
            18
    MISSING_ID
            19
    12 rows selected.Or:
    with t as
              select  1 as id from dual union all
              select  2 as id from dual union all
              select  3 as id from dual union all
              select  5 as id from dual union all
              select  8 as id from dual union all
              select 10 as id from dual union all
              select 11 as id from dual union all
              select 20 as id from dual
    select  id_start + level - 1 missing_id
       from  (
              select  min(id) id_start,
                      max(id) id_end
                from  t
       connect by level <= id_end - id_start
    minus
    select  id
       from  t
    MISSING_ID
             4
             6
             7
             9
            12
            13
            14
            15
            16
            17
            18
    MISSING_ID
            19
    12 rows selected.SY.

  • Diff b/w primary key and unique key?

    what is the diff b/w primary key and unique key?

    Hi,
    With respect to functionality both are same.
    But in ABAP we only have Primary key for the Database tables declared in the Data Dictionary.
    Unique is generally is the term used with declaring key's for internal tables.
    Both primary and Unique keys can identify one record of a table.
    Regards,
    Sesh

  • Access path difference between Primary Key and Unique Index

    Hi All,
    Is there any specific way the oracle optimizer treats Primary key and Unique index differently?
    Oracle Version
    SQL> select * from v$version;
    BANNER
    Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
    PL/SQL Release 11.2.0.3.0 - Production
    CORE    11.2.0.3.0      Production
    TNS for IBM/AIX RISC System/6000: Version 11.2.0.3.0 - Production
    NLSRTL Version 11.2.0.3.0 - Production
    SQL> Sample test data for Normal Index
    SQL> create table t_test_tab(col1 number, col2 number, col3 varchar2(12));
    Table created.
    SQL> create sequence seq_t_test_tab start with 1 increment by 1 ;
    Sequence created.
    SQL>  insert into t_test_tab select seq_t_test_tab.nextval, round(dbms_random.value(1,999)) , 'B'||round(dbms_random.value(1,50))||'A' from dual connect by level < 100000;
    99999 rows created.
    SQL> commit;
    Commit complete.
    SQL> exec dbms_stats.gather_table_stats(USER_OWNER','T_TEST_TAB',cascade => true);
    PL/SQL procedure successfully completed.
    SQL> select col1 from t_test_tab;
    99999 rows selected.
    Execution Plan
    Plan hash value: 1565504962
    | Id  | Operation         | Name       | Rows  | Bytes | Cost (%CPU)| Time     |
    |   0 | SELECT STATEMENT  |            | 99999 |   488K|    74   (3)| 00:00:01 |
    |   1 |  TABLE ACCESS FULL| T_TEST_TAB | 99999 |   488K|    74   (3)| 00:00:01 |
    Statistics
              1  recursive calls
              0  db block gets
           6915  consistent gets
            259  physical reads
              0  redo size
        1829388  bytes sent via SQL*Net to client
          73850  bytes received via SQL*Net from client
           6668  SQL*Net roundtrips to/from client
              0  sorts (memory)
              0  sorts (disk)
          99999  rows processed
    SQL> create index idx_t_test_tab on t_test_tab(col1);
    Index created.
    SQL> exec dbms_stats.gather_table_stats('USER_OWNER','T_TEST_TAB',cascade => true);
    PL/SQL procedure successfully completed.
    SQL> select col1 from t_test_tab;
    99999 rows selected.
    Execution Plan
    Plan hash value: 1565504962
    | Id  | Operation         | Name       | Rows  | Bytes | Cost (%CPU)| Time     |
    |   0 | SELECT STATEMENT  |            | 99999 |   488K|    74   (3)| 00:00:01 |
    |   1 |  TABLE ACCESS FULL| T_TEST_TAB | 99999 |   488K|    74   (3)| 00:00:01 |
    Statistics
              1  recursive calls
              0  db block gets
           6915  consistent gets
              0  physical reads
              0  redo size
        1829388  bytes sent via SQL*Net to client
          73850  bytes received via SQL*Net from client
           6668  SQL*Net roundtrips to/from client
              0  sorts (memory)
              0  sorts (disk)
          99999  rows processed
    SQL> Sample test data when using Primary Key
    SQL> create table t_test_tab1(col1 number, col2 number, col3 varchar2(12));
    Table created.
    SQL> create sequence seq_t_test_tab1 start with 1 increment by 1 ;
    Sequence created.
    SQL> insert into t_test_tab1 select seq_t_test_tab1.nextval, round(dbms_random.value(1,999)) , 'B'||round(dbms_random.value(1,50))||'A' from dual connect by level < 100000;
    99999 rows created.
    SQL> commit;
    Commit complete.
    SQL> exec dbms_stats.gather_table_stats('USER_OWNER','T_TEST_TAB1',cascade => true);
    PL/SQL procedure successfully completed.
    SQL> select col1 from t_test_tab1;
    99999 rows selected.
    Execution Plan
    Plan hash value: 1727568366
    | Id  | Operation         | Name        | Rows  | Bytes | Cost (%CPU)| Time     |
    |   0 | SELECT STATEMENT  |             | 99999 |   488K|    74   (3)| 00:00:01 |
    |   1 |  TABLE ACCESS FULL| T_TEST_TAB1 | 99999 |   488K|    74   (3)| 00:00:01 |
    Statistics
              1  recursive calls
              0  db block gets
           6915  consistent gets
              0  physical reads
              0  redo size
        1829388  bytes sent via SQL*Net to client
          73850  bytes received via SQL*Net from client
           6668  SQL*Net roundtrips to/from client
              0  sorts (memory)
              0  sorts (disk)
          99999  rows processed
    SQL> alter table t_test_tab1 add constraint pk_t_test_tab1 primary key (col1);
    Table altered.
    SQL> exec dbms_stats.gather_table_stats('USER_OWNER','T_TEST_TAB1',cascade => true);
    PL/SQL procedure successfully completed.
    SQL> select col1 from t_test_tab1;
    99999 rows selected.
    Execution Plan
    Plan hash value: 2995826579
    | Id  | Operation            | Name           | Rows  | Bytes | Cost (%CPU)| Time     |
    |   0 | SELECT STATEMENT     |                | 99999 |   488K|    59   (2)| 00:00:01 |
    |   1 |  INDEX FAST FULL SCAN| PK_T_TEST_TAB1 | 99999 |   488K|    59   (2)| 00:00:01 |
    Statistics
              1  recursive calls
              0  db block gets
           6867  consistent gets
              0  physical reads
              0  redo size
        1829388  bytes sent via SQL*Net to client
          73850  bytes received via SQL*Net from client
           6668  SQL*Net roundtrips to/from client
              0  sorts (memory)
              0  sorts (disk)
          99999  rows processed
    SQL> If you see here the even though statistics were gathered,
         * In the 1st table T_TEST_TAB, the table is still using FULL table access after creation of index.
         * And in the 2nd table T_TEST_TAB1, table is using PRIMARY KEY as expected.
    Any comments ??
    Regards,
    BPat

    Thanks.
    Yes, ignored the NOT NULL part.Did a test and now it is working as expected
    SQL>  create table t_test_tab(col1 number not null, col2 number, col3 varchar2(12));
    Table created.
    SQL>
    create sequence seq_t_test_tab start with 1 increment by 1 ;SQL>
    Sequence created.
    SQL> insert into t_test_tab select seq_t_test_tab.nextval, round(dbms_random.value(1,999)) , 'B'||round(dbms_random.value(1,50))||'A' from dual connect by level < 100000;
    99999 rows created.
    SQL> commit;
    Commit complete.
    SQL>  exec dbms_stats.gather_table_stats('GREP_OWNER','T_TEST_TAB',cascade => true);
    PL/SQL procedure successfully completed.
    SQL>  set autotrace traceonly
    SQL>  select col1 from t_test_tab;
    99999 rows selected.
    Execution Plan
    Plan hash value: 1565504962
    | Id  | Operation         | Name       | Rows  | Bytes | Cost (%CPU)| Time     |
    |   0 | SELECT STATEMENT  |            | 99999 |   488K|    74   (3)| 00:00:01 |
    |   1 |  TABLE ACCESS FULL| T_TEST_TAB | 99999 |   488K|    74   (3)| 00:00:01 |
    Statistics
              1  recursive calls
              0  db block gets
           6912  consistent gets
              0  physical reads
              0  redo size
        1829388  bytes sent via SQL*Net to client
          73850  bytes received via SQL*Net from client
           6668  SQL*Net roundtrips to/from client
              0  sorts (memory)
              0  sorts (disk)
          99999  rows processed
    SQL>  create index idx_t_test_tab on t_test_tab(col1);
    Index created.
    SQL>  exec dbms_stats.gather_table_stats('GREP_OWNER','T_TEST_TAB',cascade => true);
    PL/SQL procedure successfully completed.
    SQL>  select col1 from t_test_tab;
    99999 rows selected.
    Execution Plan
    Plan hash value: 4115006285
    | Id  | Operation            | Name           | Rows  | Bytes | Cost (%CPU)| Time     |
    |   0 | SELECT STATEMENT     |                | 99999 |   488K|    63   (2)| 00:00:01 |
    |   1 |  INDEX FAST FULL SCAN| IDX_T_TEST_TAB | 99999 |   488K|    63   (2)| 00:00:01 |
    Statistics
              1  recursive calls
              0  db block gets
           6881  consistent gets
              0  physical reads
              0  redo size
        1829388  bytes sent via SQL*Net to client
          73850  bytes received via SQL*Net from client
           6668  SQL*Net roundtrips to/from client
              0  sorts (memory)
              0  sorts (disk)
          99999  rows processed
    SQL>

  • Difference between primary key and primary index

    Dear All,
             Hi... .Could you pls tell me the difference between primary key and primary index.
    Thanks...

    Hi,
    Primary Key : It is one which makes an entry of the field unique.No two distinct rows in a table can have the same value (or combination of values) in those columns.
    Eg: first entry is 111, if you again enter value 111 , it doesnot allow 111 again. similarly for the strings or characters or numc etc. Remember that for char or numc or string 'NAME' is not equal to 'name'.
    Primary Index: this is related to the performance .A database index is a data structure that improves the speed of operations in a table. Indices can be created using one or more columns, providing the basis for both rapid random lookups and efficient ordering of access to records. The disk space required to store the index is typically less than the storage of the table (since indices usually contain only the key-fields according to which the table is to be arranged, and excludes all the other details in the table), yielding the possibility to store indices into memory from tables that would not fit into it. In a relational database an index is a copy of part of a table. Some databases extend the power of indexing by allowing indices to be created on functions or expressions. For example, an index could be created on upper(last_name), which would only store the uppercase versions of the last_name field in the index.
    In a database , we may have a large number of records. At the time of retrieving data from the database based on a condition , it is a burden to the db server. so whenever we create a primary key , a primary index is automatically created by the system.
    If you want to maintain indices on other fields which are frequently used in where condition then you can create secondary indices.
    Reward points if helpful.
    Thanks,
    Sirisha..

  • What is the diffrence between Row id and primary key ?

    dear all
    my question is about creating materialized views parameters (With Rowid and
    With Primary kry)
    my master table contains a primary key
    and i created my materialized view as follow:
    CREATE MATERIALIZED VIEW LV_BULLETIN_MV
    TABLESPACE USERS
    NOCACHE
    LOGGING
    NOCOMPRESS
    NOPARALLEL
    REFRESH FAST ON DEMAND
    WITH PRIMARY KEY
    AS
    SELECT
    BCODE ID, BTYPE BTYPE_ID,
    BDATE THE_DATE,SYMBOL_CODE STOCK_CODE,
    BHEAD DESC_E, BHEADARB DESC_A,
    BMSG TEXT_E, BMSGARB TEXT_A,
    BURL URL, BTIME THE_TIME
    FROM BULLETIN@egid_sefit;
    I need to know is there a diffrence between using (with row id) and (with primary key) on the performance of the query?

    Hi again,
    fast refreshing complex views based on rowids, according to the previous subject.
    (You're example shows that) are not possible.
    Complex remote (replication) snapshots cannot be based on Rowid too.
    for 10.1
    http://download-west.oracle.com/docs/cd/B14117_01/server.101/b10759/statements_6002.htm#sthref5054
    for 10.2
    http://download-uk.oracle.com/docs/cd/B19306_01/server.102/b14200/statements_6002.htm#sthref6873
    So I guess (didn't check it) that this applies ONLY to replication snapshots.
    This is not documented clearly though (documentation bug ?!)
    Documentation states that the following is generally not possible with Rowid MVIEWS:
    Distinct or aggregate functions
    GROUP BY or CONNECT BY clauses
    Subqueries
    Joins
    Set operations
    Rowid materialized views are not eligible for fast refresh after a master table reorganization until a complete refresh has been performed.
    The main purpose of my statements was to try to give a few tips how to avoid common problems with this complex subject, like for example: being able to CREATE an MVIEW with fast refresh clause does not really guarantee that it will refresh fast in the long run (reorganisation, partition changes) if ROWID based, further the rowid mviews have limitations according to the documentation (no group by, no connect by, link see above) plus fast refresh means only to use filter columnns of the mview logs, plus for aggregates you need additional count (*) pseudo columns.
    kind regards
    Karsten

  • Primary key vs Secondary key - why would a rpt hit one as to the other?

    Post Author: kevans
    CA Forum: Data Connectivity and SQL
    Here's an issue that surfaced when using CRW10, happens with XI as well, but not an issue with CRW8 - each one is hitting the same SQL Server db.
    I discovered something today and I'm not sure if this might be the road to a solution, however, I don't know enough about SQL Server and/or Crystal.  First, my reports seem fairly simple in nature, I don't think I'm pulling a million rows of data, maybe but doubt it.  So I run report ABC and I see blocking issues in SQL Server Enterprise Mgr.  If I run report XYZ that isn't too much different than ABC, I do not see blocking issues.  Hmm, what could be different?  In SQL-Mgr when I look at the SPID info generated by the report I can see the tables the report is referencing and below is what I discovered.
    The one difference I see is under the "Index" column - the report blocking shows "XPKcall_req" where call_req is the table I'm pulling from.  The report that IS NOT blocking shows call_req_x0.  I checked with our dba and he wasn't sure, other than to say XPK is the primary key index.  Okay, then why is one report hitting the primary key index (whatever that is) and the other isn't?  In Crystal I'm not sure how to tell it to stop doing this, I tried shaking my finger and yelling but like my kids this does little.
    Any ideas, with the report that is?

    Post Author: kevans
    CA Forum: Data Connectivity and SQL
    Here's an issue that surfaced when using CRW10, happens with XI as well, but not an issue with CRW8 - each one is hitting the same SQL Server db.
    I discovered something today and I'm not sure if this might be the road to a solution, however, I don't know enough about SQL Server and/or Crystal.  First, my reports seem fairly simple in nature, I don't think I'm pulling a million rows of data, maybe but doubt it.  So I run report ABC and I see blocking issues in SQL Server Enterprise Mgr.  If I run report XYZ that isn't too much different than ABC, I do not see blocking issues.  Hmm, what could be different?  In SQL-Mgr when I look at the SPID info generated by the report I can see the tables the report is referencing and below is what I discovered.
    The one difference I see is under the "Index" column - the report blocking shows "XPKcall_req" where call_req is the table I'm pulling from.  The report that IS NOT blocking shows call_req_x0.  I checked with our dba and he wasn't sure, other than to say XPK is the primary key index.  Okay, then why is one report hitting the primary key index (whatever that is) and the other isn't?  In Crystal I'm not sure how to tell it to stop doing this, I tried shaking my finger and yelling but like my kids this does little.
    Any ideas, with the report that is?

  • Performance: index vs. primary key

    For reasons beyond my control, I have an Oracle database with no primary keys. Fields that would likely be primary keys, however, are indexed.
    Is there any reason to believe that database performance will improve if I do add primary keys?
    If yes, why?
    Thank you!
    -Brent

    Primary keys provide unique values and an in built index on thecolumn. Since the fields are indexed converting them to primary keys shall not affect the performance.Yes, if u want unique values they can be defined as Primary Keys.
    However if these fields are VARCHAR2 with large size then an index will not improve the performance. You can look at creating new PK as numeric fields with a Sequence.
    <BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Brent Christensen ([email protected]):
    For reasons beyond my control, I have an Oracle database with no primary keys. Fields that would likely be primary keys, however, are indexed.
    Is there any reason to believe that database performance will improve if I do add primary keys?
    If yes, why?
    Thank you!
    -Brent<HR></BLOCKQUOTE>
    null

Maybe you are looking for