Analysis on the specific execution process of an insert statement in MySQL 8.0 (3)

Code version ：mysql 8.0.22

programing language ：c++ && c++11 && c++14 && c++17

Last article ：mysql 8.0 One insert Analysis of the specific execution process of the statement ( Two )_ A ray of sunshine blog -CSDN Blog

It mainly introduces the storage engine , This chapter mainly introduces insert Which interfaces need to be called when a statement has a secondary index , The order of calling interfaces is as follows ：

The following interfaces can be understood basically from the source code , Don't repeat .

Let's take clustered indexes and secondary indexes as examples , Clustered index The calling interface is as follows ：

| > row_ins_clust_index_entry
| | > row_ins_clust_index_entry_low
| | | > btr_cur_optimistic_insert
| | | | > btr_cur_ins_lock_and_undo
| | | | | > trx_undo_report_row_operation
| | | | | | > trx_undo_page_report_insert
| | | | | | | > trx_undo_page_set_next_prev_and_add
| | | | | | | | > trx_undof_page_add_undo_rec_log

| | | | > page_cur_tuple_insert
| | | | | > rec_convert_dtuple_to_rec
            > rec_convert_dtuple_to_rec_new
            > rec_convert_dtuple_to_rec_old
              > rec_convert_dtuple_to_rec_comp
            
| | | | | > page_cur_insert_rec_low
            > page_cur_insert_rec_write_log

(12)、row_ins_clust_index_entry : Insert entry To a clustered index , Would call 13 The interface
(13)、row_ins_clust_index_entry_low : Try to entry Insert into clustered index , Ignore foreign key constraints .
(14)、btr_cur_optimistic_insert : Insert a page To an index tree
(15)、btr_cur_ins_lock_and_undo : Check lock And write undo log
(16)、page_cur_tuple_insert : Take one record Append to current page, Need and 17 The function in completes
(17)、page_cur_insert_rec_low : Take one record Append to current page, Write uncompressed

Secondary indexes The calling interface is as follows ：

| > row_ins_sec_index_entry
| | > row_ins_sec_index_entry_low
| | | > btr_cur_search_to_nth_level
        > ibuf_should_try
| | | > row_ins_scan_sec_index_for_duplicate

(18)、row_ins_sec_index_entry : Insert... In the secondary index entry
(19)、row_ins_sec_index_entry_low : Try to entry Insert secondary index . If you find a record with exactly the same field , The other record must be marked as deleted , Then insert it into the secondary index
(20)、btr_cur_search_to_nth_level : In the index tree Given in level Find the current location on
(21)、row_ins_scan_sec_index_for_duplicate : Scans for unique nonclustered indexes at a given index entry , To determine whether the key value of the item has a uniqueness conflict . Set the shared lock for possible duplicate records

Last , After all breakpoints have been executed , Use bt The command prints the stack information , Because there are too many breakpoints , Some of the main functions are printed , as follows ：

(gdb) bt
#0  btr_cur_optimistic_insert (flags=0, cursor=0x7fffe83d4ae0, offsets=0x7fffe83d4a78, 
    heap=0x7fffe83d4a70, entry=0x7fff300cb370, rec=0x7fffe83d4a80, big_rec=0x7fffe83d4a68, 
    thr=0x7fff3029c6f8, mtr=0x7fffe83d50a0)
    at /storage/innobase/btr/btr0cur.cc:2833
#1  0x000055555a4c7571 in row_ins_clust_index_entry_low (flags=0, mode=2, index=0x7fff3028a640, 
    n_uniq=1, entry=0x7fff300cb370, thr=0x7fff3029c6f8, dup_chk_only=false)
    at storage/innobase/row/row0ins.cc:2518
#2  0x000055555a4c945c in row_ins_clust_index_entry (index=0x7fff3028a640, entry=0x7fff300cb370, 
    thr=0x7fff3029c6f8, dup_chk_only=false)
    at /storage/innobase/row/row0ins.cc:3097
#3  0x000055555a4c9c14 in row_ins_index_entry (index=0x7fff3028a640, entry=0x7fff300cb370, 
    [email protected]: 0, thr=0x7fff3029c6f8)
    at /storage/innobase/row/row0ins.cc:3289
#4  0x000055555a4ca26f in row_ins_index_entry_step (node=0x7fff3029c338, thr=0x7fff3029c6f8)
    at /storage/innobase/row/row0ins.cc:3425
#5  0x000055555a4ca616 in row_ins (node=0x7fff3029c338, thr=0x7fff3029c6f8)
    at /storage/innobase/row/row0ins.cc:3544
#6  0x000055555a4caa92 in row_ins_step (thr=0x7fff3029c6f8)
    at /storage/innobase/row/row0ins.cc:3668
#7  0x000055555a4ea804 in row_insert_for_mysql_using_ins_graph (mysql_rec=0x7fff302892c8 "\376\005", 
    prebuilt=0x7fff3029b830) at /storage/innobase/row/row0mysql.cc:1581
#8  0x000055555a4eae9a in row_insert_for_mysql (mysql_rec=0x7fff302892c8 "\376\005", 
    prebuilt=0x7fff3029b830) at /storage/innobase/row/row0mysql.cc:1711
#9  0x000055555a2a9ad9 in ha_innobase::write_row (this=0x7fff30287bf8, record=0x7fff302892c8 "\376\005")
    at /storage/innobase/handler/ha_innodb.cc:8629
#10 0x0000555558d4ace2 in handler::ha_write_row (this=0x7fff30287bf8, buf=0x7fff302892c8 "\376\005")
    at /sql/handler.cc:7831
#11 0x00005555590a14a7 in write_record (thd=0x7fff30001040, table=0x7fff30287270, info=0x7fffe83d64f0, 
    update=0x7fffe83d6570) at /sql/sql_insert.cc:2148
#12 0x000055555909cb7e in Sql_cmd_insert_values::execute_inner (this=0x7fff302becc8, thd=0x7fff30001040)
    at /sql/sql_insert.cc:633
#13 0x00005555589ff8fc in Sql_cmd_dml::execute (this=0x7fff302becc8, thd=0x7fff30001040)
    at /sql/sql_select.cc:612
#14 0x000055555897bd6e in mysql_execute_command (thd=0x7fff30001040, first_level=true)
    at /sql/sql_parse.cc:3420
#15 0x00005555589810b9 in dispatch_sql_command (thd=0x7fff30001040, parser_state=0x7fffe83d7b90)
    at /sql/sql_parse.cc:4988
#16 0x0000555558977226 in dispatch_command (thd=0x7fff30001040, com_data=0x7fffe83d8b80, 
    command=COM_QUERY) at /sql/sql_parse.cc:1836
#17 0x00005555589756df in do_command (thd=0x7fff30001040)
    at /sql/sql_parse.cc:1320
#18 0x0000555558b6ee3d in handle_connection (arg=0x55556006bbe0)
    at /sql/conn_handler/connection_handler_per_thread.cc:301
#19 0x000055555aa337b6 in pfs_spawn_thread (arg=0x55555fee7ae0)
    at /storage/perfschema/pfs.cc:2900
--Type <RET> for more, q to quit, c to continue without paging--
#20 0x00007ffff7f95609 in start_thread (arg=<optimized out>) at pthread_create.c:477
#21 0x00007ffff76e0293 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95

Only this and nothing more , stay MySQL in insert One record The basic process of has been sorted out , The process is quite clear , Those who have primary database experience can sort it out .

The next few articles are mainly about MySQL in redo.log Medium mtr.