db2 sort

Recently has been doing database optimization this business, found themselves a lot of DB2 commands are forgotten, and even useless, and sometimes become a bottleneck in the efficiency of the work, 工欲善其事, its prerequisite, so did the following summary:1. Open the Command Line window#db2cmd2. Open the control center# Db2cmd DB2CC3. Open the Command editorDb2cmd Db2ce===== Operation Database Command =====4. Start the DB instance#db2start5. Stop the DB i

1. Open the Command Line window#db2cmd2. Open the control center# Db2cmd DB2CC3. Open the Command editorDb2cmd Db2ce===== Operation Database Command =====4. Start the DB instance#db2start5. Stop the DB instance#db2stopIf you cannot stop the database due to the active connection, execute DB2 force application before running db2stop all to/db2stop force6. Create a database#db2 Create DB [dbname]7. Connect to

Completion ID = t1Access Temp Table ID = t1 | # Columns = 2 | Relation Scan | | Prefetch: eligibleMerge Join | Access Table Name = LIAO. employee id = 2, 6 | # Columns = 4 | Skip Inserted Rows | Avoid Locking Committed Data | Currently Committed for Cursor Stability | May participant in Scan Sharing structures | Scan may start anywhere and wrap, for completion | Fast scan, for purposes of scan sharing management | Scan can be throttled in scan sharing management | Relation Scan | Prefetch: elig

DB2 Stored Procedure attribute description, db2 stored procedure description ProcedureName: name of the stored procedure. It cannot exist in the same database mode. Stored Procedure with the same name and number of parameters, even if the parameter type is different (In | out | inout paramName dataType ,...) : Input parameters In: input parameter, out: output parameter, inout: As input and output parameter

into the buffer pool and eventually writes each updated page to the I/O overhead on disk. The worse scenario is that there is a lot of random I/O during index maintenance. Suppose you want to insert 10,000 rows, there are 5000 pages in the buffer pool of the index, and the key values of each row to be inserted are randomly distributed across the entire key range. Well, there are 10,000 so many leaf pages (possibly more non-leaf pages) that need to go into the buffer pool so that they can be sea

DB2 obtains detailed information about the current user table, field, index, and so on. db2 current user Obtain detailed information about all tables, fields, and indexes. SELECT d. name tbName, COALESCE (d. remarks, '') tbDesc,. name columnName,. coltype columnType, decode (. nulls, 'y', '1', '0') notNull, decode (. identity, 'y', '1', '0') auto,. longlength width,. scale precision, COALESCE (. remarks,

Label:Connect reset should terminate the database connection with a commit action terminate should be able to terminate this client-initiated process and release resources Terminate is a command, in addition to disconnecting, it also terminates the CLP (command line processor) background process, which is the common db2bp.connect reset is the SQL statement quit Exit CLP, but the database connection is constantly open connect reset disconnects the database but does not exit the CLPterminate

The fast sorting method mainly utilizes a method of arrays to Arrays.sort () implementation. Bubble method is used to compare the traversal array, through the constant comparison of the minimum or maximum value of a single traversal. The Select Sort method is to use the first data of the array as the largest or smallest value, and then output the ordered array by comparing the loops. The insertion sort i

This article is a detailed summary of DB2 Common operation commands, to share with you. For the use of DB2 friends can refer to the following. The DB2 database management client does not have a control center since the v9.7 version, but instead uses data Studio client. License keys are not applied during the installation of the

following command: Db2 "update monitor switches using sort on" Then, let the application run for a while, and enter: Db2 "get snapshot for database on DBNAME" Based on this output, you can calculate the number of sorting tasks for each transaction, and calculate the percentage of sorting that overflows the memory that can be used for sorting. SortsPerTransaction

adjust the memory content and perform any necessary operations to move partitions into or out of memory. Next, you can process multiple parallel tuples in the test table based on the partitions in the resident memory, to overflow the parallel tuples in the hash join partition of the temporary table. Finally, overflow partitions are processed in parallel. Each task processes one or more overflow partitions.2.2 which connection method is selected?So far, we have discussed different connection met

The preceding is the comparison sorting algorithm, mainly bubble sort , select Sort , insert sort , merge sort , heap sort , quick Sort etc.Non-comparison sorting algorithm: counting sort