📄 db2isolationlevels.out
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ij> -- single user test for the various isolation levels-- also notice in the runtimestatistics output that Fetch Size is 16 for various isolation levels ie we are doing bulk fetch for all isolation levels-- this will test the fix for bug 5953 - which is to enable bulk fetching for RR and serializable isolation levels as well.prepare getIsolation as 'values current isolation';ij> autocommit off;ij> call SYSCS_UTIL.SYSCS_SET_RUNTIMESTATISTICS(1);0 rows inserted/updated/deletedij> maximumdisplaywidth 2000;ij> -- create a tablecreate table t1(c1 int not null constraint asdf primary key);0 rows inserted/updated/deletedij> commit;ij> -- insert a rowinsert into t1 values 1;1 row inserted/updated/deletedij> -- verify table scan gets row lock at read committedselect * from t1;C1 -----------1 ij> values SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS();1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Statement Name: nullStatement Text: -- verify table scan gets row lock at read committedselect * from t1Parse Time: 0Bind Time: 0Optimize Time: 0Generate Time: 0Compile Time: 0Execute Time: 0Begin Compilation Timestamp : nullEnd Compilation Timestamp : nullBegin Execution Timestamp : nullEnd Execution Timestamp : nullStatement Execution Plan Text: Index Scan ResultSet for T1 using constraint ASDF at read committed isolation level using instantaneous share row locking chosen by the optimizerNumber of opens = 1Rows seen = 1Rows filtered = 0Fetch Size = 16 constructor time (milliseconds) = 0 open time (milliseconds) = 0 next time (milliseconds) = 0 close time (milliseconds) = 0 next time in milliseconds/row = 0scan information: Bit set of columns fetched={0} Number of columns fetched=1 Number of deleted rows visited=0 Number of pages visited=1 Number of rows qualified=1 Number of rows visited=1 Scan type=btree Tree height=1 start position: None stop position: None qualifiers:Noneij> -- verify SET ISOLATION commits and changes isolation levelset isolation RR;0 rows inserted/updated/deletedij> execute getIsolation;1 ----RR ij> -- rollback should find nothing to undorollback;ij> select * from t1;C1 -----------1 ij> values SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS();1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Statement Name: nullStatement Text: select * from t1Parse Time: 0Bind Time: 0Optimize Time: 0Generate Time: 0Compile Time: 0Execute Time: 0Begin Compilation Timestamp : nullEnd Compilation Timestamp : nullBegin Execution Timestamp : nullEnd Execution Timestamp : nullStatement Execution Plan Text: Index Scan ResultSet for T1 using constraint ASDF at serializable isolation level using share table locking chosen by the optimizerNumber of opens = 1Rows seen = 1Rows filtered = 0Fetch Size = 16 constructor time (milliseconds) = 0 open time (milliseconds) = 0 next time (milliseconds) = 0 close time (milliseconds) = 0 next time in milliseconds/row = 0scan information: Bit set of columns fetched={0} Number of columns fetched=1 Number of deleted rows visited=0 Number of pages visited=1 Number of rows qualified=1 Number of rows visited=1 Scan type=btree Tree height=1 start position: None stop position: None qualifiers:Noneij> set isolation reset;0 rows inserted/updated/deletedij> execute getIsolation;1 ----ij> -- verify SET ISOLATION commits and changes isolation levelset isolation read committed;0 rows inserted/updated/deletedij> execute getIsolation;1 ----CS ij> -- rollback should find nothing to undorollback;ij> select * from t1;C1 -----------1 ij> values SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTICS();1 ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Statement Name: nullStatement Text: select * from t1Parse Time: 0Bind Time: 0Optimize Time: 0Generate Time: 0Compile Time: 0Execute Time: 0Begin Compilation Timestamp : nullEnd Compilation Timestamp : nullBegin Execution Timestamp : nullEnd Execution Timestamp : nullStatement Execution Plan Text: Index Scan ResultSet for T1 using constraint ASDF at read committed isolation level using instantaneous share row locking chosen by the optimizerNumber of opens = 1Rows seen = 1Rows filtered = 0Fetch Size = 16 constructor time (milliseconds) = 0 open time (milliseconds) = 0 next time (milliseconds) = 0 close time (milliseconds) = 0 next time in milliseconds/row = 0scan information: Bit set of columns fetched={0} Number of columns fetched=1 Number of deleted rows visited=0 Number of pages visited=1 Number of rows qualified=1 Number of rows visited=1 Scan type=btree Tree height=1 start position: None stop position: None qualifiers:None
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