1. 14 May, 2007 1 commit
  2. 11 May, 2007 4 commits
    • dlenev@mockturtle.local's avatar
    • dlenev@mockturtle.local's avatar
      Merge bk-internal.mysql.com:/home/bk/mysql-5.0-runtime · d5dbdd98
      dlenev@mockturtle.local authored
      into  mockturtle.local:/home/dlenev/src/mysql-5.0-cts-3
      d5dbdd98
    • dlenev@mockturtle.local's avatar
      Fix for: · 8b93e52e
      dlenev@mockturtle.local authored
        Bug #20662 "Infinite loop in CREATE TABLE IF NOT EXISTS ... SELECT
                    with locked tables"
        Bug #20903 "Crash when using CREATE TABLE .. SELECT and triggers"
        Bug #24738 "CREATE TABLE ... SELECT is not isolated properly"
        Bug #24508 "Inconsistent results of CREATE TABLE ... SELECT when
                    temporary table exists"
       
      Deadlock occured when one tried to execute CREATE TABLE IF NOT
      EXISTS ... SELECT statement under LOCK TABLES which held
      read lock on target table.
      Attempt to execute the same statement for already existing
      target table with triggers caused server crashes.
      Also concurrent execution of CREATE TABLE ... SELECT statement
      and other statements involving target table suffered from
      various races (some of which might've led to deadlocks).
      Finally, attempt to execute CREATE TABLE ... SELECT in case
      when a temporary table with same name was already present
      led to the insertion of data into this temporary table and
      creation of empty non-temporary table.
       
      All above problems stemmed from the old implementation of CREATE
      TABLE ... SELECT in which we created, opened and locked target
      table without any special protection in a separate step and not
      with the rest of tables used by this statement.
      This underminded deadlock-avoidance approach used in server
      and created window for races. It also excluded target table
      from prelocking causing problems with trigger execution.
        
      The patch solves these problems by implementing new approach to
      handling of CREATE TABLE ... SELECT for base tables.
      We try to open and lock table to be created at the same time as
      the rest of tables used by this statement. If such table does not
      exist at this moment we create and place in the table cache special
      placeholder for it which prevents its creation or any other usage
      by other threads.
      
      We still use old approach for creation of temporary tables.
      
      Also note that we decided to postpone introduction of some tests
      for concurrent behaviour of CREATE TABLE ... SELECT till 5.1.
      The main reason for this is absence in 5.0 ability to set @@debug
      variable at runtime, which can be circumvented only by using several
      test files with individual .opt files. Since the latter is likely
      to slowdown test-suite unnecessary we chose not to push this tests
      into 5.0, but run them manually for this version and later push
      their optimized version into 5.1
      8b93e52e
    • kostja@vajra.(none)'s avatar
      Cleanup: now that we have Lex_input_stream, finish the transition · ad609d6e
      kostja@vajra.(none) authored
      by moving yet another relevant flag to it from struct LEX.
      ad609d6e
  3. 10 May, 2007 4 commits
  4. 08 May, 2007 4 commits
  5. 07 May, 2007 2 commits
  6. 02 May, 2007 2 commits
  7. 01 May, 2007 2 commits
  8. 30 Apr, 2007 9 commits
  9. 29 Apr, 2007 12 commits