mysql trigger tutorial

, Truncat The e table is the process of rebuilding the IBD file during the MySQL process interruption, resulting in IBD file corruption.7, re-create a database, the innodb_file_per_table = 1 parameters are removed, all tables share an IBD file.Repeat the test above and run for 15 minutes without a database table corruption.Analysis conclusioninnodb_file_per_table = 1, using truncate will recreate the IBD file, if the process mysqld process unexpectedl

1. Create two new test tables, number tables, and users tables.Number table field (Id,number,name)Users table field (Id,name)2. Open the Users table, design a trigger for a tableName (custom), trigger (after), select Insert3. Edit the text in the definition saveBeginUpdate numberSet Number = (select COUNT (*) from tusers), name= new.name where id=1;End4. Test, the Users table data is constantly added, Numbe

Mysql trigger jumps out of the current loop method set @ num = @ UnitLength/3; label: while I Type = 'smscall' and unit_sid_fk = @ length); set @ sms_counts = (select sms_counts from sms_config where sms _Type = 'smscall' and unit_sid_fk = @ length); if @ sms_content is not null then insert into sms_task set mt_at_time = @ date, mt_content = @ sms_content, unit _Sid_fk = @ unit_sid_fk, mt _Dst_num = @ callt

MySQL condition using an OR query does not trigger an index?

t_afterinsert_on_tab1; CREATE TRIGGER T_AFTERINSERT_ON_TAB1 After INSERT on TAB1 For each ROW BEGIN Insert into TAB2 (tab2_id) values (new.tab1_id); End; Test INSERT into TAB1 (tab1_id) VALUES (' 0001 '); Look at the results. SELECT * from TAB1; SELECT * from TAB2; Example2: Create Trigger: t_afterdelete_on_tab1 function: Delete tab1 table record automatically remove corresponding record in TA

MySQL under INSERT and update triggers can no longer use the update and insert operations, the official explanation is to prevent the death cycle, the solution is directly to new in the field assignment, but also very convenient, but also explains the technology of MySQL to be strengthened, After all, they can be implemented by the functions of MSSQL, to you this will be a problem. The code is

forEach rowbegin DeclareCount1int(Ten); SetCount1=(Select Count(*) fromproduct); Insert intoOperateValues(Count1,'Insert', now ()); End delimiter; #创建product_af_update触发器delimiter Create TriggerProduct_af_update afterUpdate onProduct forEach rowbegin DeclareCount2int(Ten); SetCount2=(Select Count(*) fromproduct); Insert intoOperateValues(Count2,'Update', now ()); End delimiter; #创建product_af_delete触发器delimiter Create TriggerProduct_af_delete afterDelete onProduct forEach rowbegin DeclareCo

The argument is that an or is present in the Where condition and the index is not used My test results are as follows: Mysql> explain select * from emp where ename= "Dsleos" or ename= "Saesad" \g*************************** 1. Row *************************** id:1 select_type:simple table:emp type:rangepossible_keys:e_i key:e_i key_len:62 ref:null rows:2 extra:using where1 row in Set

long as the separation of two execution time is enough.A little bit of personal experience, hope to help everyone.Individual environment yo often check show variables like '%event_scheduler% '; make sure this database permission is already open OKTo open the Event_scheduler SQL command:SET GLOBAL event_scheduler = on;SET @ @global. Event_scheduler = on;SET GLOBAL event_scheduler = 1;SET @ @global. Event_scheduler = 1;Instead, close the Event_scheduler command:SET GLOBAL event_scheduler = OFF;SE

MySQL Trigger Simple instance~ ~ Grammar ~ ~CREATE TRIGGER trigger name > --the trigger must have a name, a maximum of 64 characters, and may be appended with a delimiter. It is basically like naming other objects in MySQL.{ befo

Tags: Pre view using CTI AddClass string Linu dead Loop iterOne requirement for recent projects is to limit the number of operations logs to 100,000, and more than 100,000 to delete the oldest one, saving no more than 100,000 of the logs in the database.My first thought was to do it through a trigger and execute the following SQL in the database: Delimiter $ Create trigger limitlog beforeinsert on Operation

DROPTABLEifEXISTStb; CREATETABLEtb (BHCHAR (16), contentVARCHAR (20), 'date' DATETIME, valINT); values (8) DECLAREbh_idCHAR (16) DECLAREnumberINT (1) values... mysql Drop table if EXISTS tb;Create table tb (bh char (16), content VARCHAR (20 ),DateDATETIME, val INT ); Create trigger tri_NewBH before insert on tbFOR EACH ROWBEGINDECLARE dt CHAR (8)DECLARE bh_id CHAR (16)DECLARE number INT (1)DECLARE n

Tags: mysql triggers -- added createtriggeryqhl_htjs_b_htjbxx_insertbeforeinserton table name foreachrow begin if (NEW. F_sync_updateisnull) or (NEW. f_sync_update=0) then setnew. F_sync_update=null; -- inserting newly added records into the Operations log table insertintodata_sync_b_operator (T_name,o_type,o_date,vkeys) values (' Table name ', 1,current_timestamp,new. HTDQBH); endif; End -- modifying createtriggeryqhl_htjs_b_htjbxx_updatebeforeup

Label:MySQL Trigger Simple instanceCREATE TRIGGER --The trigger must have a name, a maximum of 64 characters, and may be appended with a delimiter. It is basically like naming other objects in MySQL.{before | After} --the trigger has a time setting for execution: it can be

Trigger an action when a table is being hacked with a trigger1. Basic statement (also need to modify delimiter)#插入前: Create Trigger T1_i_b (trigger name) before insert on info (table name) each rowbegin ... end# insert create TRIGGER t1_i_a (trigger name) After insert on

= ((select uuid ())) If this defines the trigger program, it seems to be no problem, can also add success, but the input data will be error. Can ' t Update table ' tb_user ' in stored Function/trigger because it's already used by statement which invoked this stored Function/trigger. Online says to avoid recursive triggering, updating a data cannot

MySQL Flip-flopFormat: 1, trigger definition:CREATE TRIGGER trigger_name trigger_time trigger_eventOn tbl_name for each ROW trigger_stmtDescription# Trigger_name: Trigger Name# Trigger_time: Trigger time, desirable value: before or after# Trigger_event:

corresponds to your MySQL server version for the right syntax to use near ' CREATE TRIGGER test1 After UPDATE in triggletest_triggle for each ROW BEGIN ' in line 2 */ ---The final implementation code DROP TRIGGER if EXISTS tes T1; CREATE TRIGGER test1 after UPDATE in test.triggletest_triggle for each ROW BEGIN INSERT

Label:First, create a trigger 1. Create a trigger that has an execution statement CREATE TRIGGER trigger_name before| After Trigger_event (insert| delete| UPDATE) On table_name for each ROW trigger_stmt; 2. Create a trigger with multiple execution statements DELIMITER $$ CREATE TRI