7/27/2023 0 Comments Bumpy road wattpad![]() ![]() Somehow you get even prettier when you're in my arms. “I thought I wasn't gonna see you for a long time, so it's exciting that your back. Her breath tickled his neck and he remembered he wasn't wearing a shirt. “You're making it seem like I've come back from the dead,” he laughed. Her face was in the crook of his neck and she squeezed his torso tight as he buried his nose in her hair. “You're back!” She tackled him in a hug and he returned it with as much force as she had. Sunlight filtered in through the drawn curtains above his bed. His door slammed open and he shot upright. He flopped onto the bed and passed out almost instantly. He walked into the right room this time and threw off his jacket and shirt. “I'm here now,” he whispered as he closed the door behind himself. Keith planted a soft kiss on the top of her head and stepped around the mess in her room. “I miss Keith.” She yawned and her eyes closed fully and soft snores could be heard from her. He tucked her under her blanket and she curled up into a ball. “Okay Pidgers.” Keith took the slippers off her feet and put them on the floor. “Guess again, Pidgey.” He smiled at her, and she looked at him with half lidded eyes. He removed her headphones and glasses and placed them on her bedside table. Keith walked over to her and took her laptop from her hands. She was wearing her favourite grey sleeping shorts. The strap of her tank top had fallen to the side, and her slipper-boots were covering her whole feet up to nearly her knees. Keith couldn't help but smile at how cute she was in her pajamas. She had her laptop running and looked like she had fallen asleep while using it. Her headphones were on her head and her glasses were askew. “Mattie?” He heard a small voice, and saw Pidge's tired form roll over. Select… where upper(first_name) = ‘JANIS’įinally you can have a look on Janis Best practices with MySQL Tuning here.Keith slammed his hand back down on the light switch as soon as he realized who's room he was in. Abuse of Wild Cards(*) or No Where Clause.Not always bad but have a look on this blog from Alex Rubin named “ increasing slow query performance with parallel query execution“ Consider also usage of Covering and Partial indexes.ĥ. Keep in mind that adding indexes is not always the right thing to do since you have to consider insert, update and delete operations. You also have to check if you are using the best indexes. When is each filtering predicate appliedīut also compare size of the final result set with data examined.You need to know the size of the actual data sets of each step: Her tip is to check keys and constraints, because they help creating better execution plan.Ĥ. Make sure the Optimizer can use the index, indeed functions on indexed columns can turn off index and look for implicit conversions. Have also a look on existing indexes (if multi-column, know the left leading column). Then Examine Columns in Where Clause and review selected Column and especially the usage of ‘*’ and scalar column. Get size of the table by using mysqlshow -status database Have a look on table definition and find if it’s really a table or if it’s a view. “Optimizer trace” available since version 5.6.3+ can be used with: set optimizer trace ="enabled=on"ģ. She also gave us some tips such as “Avoiding using table aliases since they don’t translate in plan”. Review the execution plan by using “explain”, “ explain extended“, “ explain FORMAT=JSON“, “ Optimizer Trace” or “ MySQL Workbench“. You can also access to the SYS Schema which is now provided by default with about 100 views.Ģ. Of course starting with MySQL 5.6 the Performance_Schema has been greatly improved and has 32 new tables in version 5.7. ![]() MysQL helps by providing Wait Events and Thread States. Monitor Wait Time and understand the total time a Query spends in Database. Finally where to stop when you start tuning a statement ?ġ. Of course tuning takes time and it’s not always the priority of the editor companies. It requires expertise in many areas, technical but also business. It sounds basic telling that it doesn’t worth adding CPU or memory when your SQL Statements have bad execution plan or are simply ineficient but that a common reflex that I already observed by customers.īut Tuning is hard, you do not always know where to start with (which statement you have to tune at first). “Tuning takes time.”, “You cannot give enough power if SQL is ineficient”, “You therefore have to monitor wait time”. She introduces her session by speaking about Challenges of Tuning. She is specialized in Performance Tuning. Janis is Senior DBA /Performance Evangelist for SolarWinds and Ace Director. Yesterday () I participated to the Janis Griffin’s session about “Top Five Query Tuning Tips” at #OOW2018. ![]()
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