Updating primary key db2

These views include columns containing statistical information that is useful to the query optimizer.

The optimizer uses information about the distribution of data in specific table or index columns if those columns are involved in row selection or table joins; it uses this information to compare the costs of different data access plans for specific queries.

So what i am trying to do is, my program uses an db2 table like a stack, selects only one row each time, updates it so any other thread cannot access it but does not make them wait entire table, they just skip updated row and select next record from table. I have written this query so far, and it cannot be processed #winces# SQL is defined to work best in sets, which means that it works best when it tries to update as many rows as possible. Note that if you are trying to get some sort of messaging queue, the DB will actually be a bottle-neck for speed; you'd be better off with an actual 'message queue'-type program (many of which have resiliency features, on top of multithreading, too)....

You need to use the same number of expressions on both sides of the comparison, when using multiple operands in a comparison.

DB2 10.5 APAR Fix list contains list of APARs shipped for each fix pack in DB2 Version 10.5 for Linux, UNIX and Windows products.

Some catalog tables have parent-child relationships. The catalog tables can be classified into broad categories based on the type of data that they store.

For example: The database manager creates and maintains two sets of system catalog views that are defined on top of the base system catalog tables.

COLUMNS view depends: select distinct substr(a.tabschema,1,16) as tabschema, substr(a.tabname,1,16) as tabname, a.type, substr(a.tbspace,1,16) as tbspace from syscat.tables a, syscat.viewdep b where = 'T' and a.tabname = b.bname and a.tabschema = b.bschema and b.btype = 'T' and b.viewname = 'COLUMNS' and b.viewschema = 'SYSCAT' connect reset TABSCHEMA TABNAME TYPE TBSPACE ---------------- ---------------- ---- ---------------- SYSIBM SYSCHECKS T SYSCATSPACE SYSIBM SYSCOLCHECKS T SYSCATSPACE SYSIBM SYSCOLPROPERTIES T SYSCATSPACE SYSIBM SYSCOLUMNS T SYSCATSPACE 4 record(s) selected.

This query is essentially the same as the underlying query generated by the DB2 Control Center when you select the Show Related action against the SYSCAT. View image at full sizeconnect to sample Retrieve information about table spaces associated with the tables that were created by user MELNYK: select substr(t.tabname, 1, 12) as tabname, t.tbspaceid as tsp_id, s.tbspacetype as tsp_type, s.datatype, s.extentsize, s.pagesize, s.dbpgname from syscat.tables t, syscat.tablespaces s where tabschema = 'MELNYK' and type = 'T' and t.tbspaceid = s.tbspaceid connect reset TABNAME TSP_ID TSP_TYPE DATATYPE EXTENTSIZE PAGESIZE DBPGNAME ------------ ------ -------- -------- ----------- ----------- ------------------ CL_SCHED 2 S A 32 4096 IBMDEFAULTGROUP DEPARTMENT 2 S A 32 4096 IBMDEFAULTGROUP EMP_ACT 2 S A 32 4096 IBMDEFAULTGROUP EMP_PHOTO 2 S A 32 4096 IBMDEFAULTGROUP EMP_RESUME 2 S A 32 4096 IBMDEFAULTGROUP EMPLOYEE 2 S A 32 4096 IBMDEFAULTGROUP IN_TRAY 2 S A 32 4096 IBMDEFAULTGROUP ORG 2 S A 32 4096 IBMDEFAULTGROUP PROJECT 2 S A 32 4096 IBMDEFAULTGROUP SALES 2 S A 32 4096 IBMDEFAULTGROUP STAFF 2 S A 32 4096 IBMDEFAULTGROUP 11 record(s) selected.connect to sample Retrieve information about each database partition and the database partition group to which it belongs: select n.dbpgname, substr(n.definer, 1, 16) as definer, n.pmap_id, n.create_time, d.dbpartitionnum, d.in_use from syscat.dbpartitiongroups n, syscat.dbpartitiongroupdef d where n.dbpgname = d.dbpgname connect reset DBPGNAME DEFINER PMAP_ID CREATE_TIME DBPARTITIONNUM IN_USE ------------------ -------...

The Severity column value of 1 is high and 4 is low.

Severity column represents the severity of the PMR at the time the APAR was opened.

The following code establishes a connection to the SAMPLE database and returns a list of all the catalog views in the SYSCAT schema: To construct meaningful queries against the catalog views, you will need to know about the columns in the available views, as well as the names and purpose of the views themselves.

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