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Agrum temperare longitudinem omnium mensarum in database, quae eundem agrum continent in MySQL

2024-07-12

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background

Ob missionem negotiorum, quidam campus ut phone_nomen multas tabulas involvit. In praesenti, multae mensae agros redundantes habent. Sed ager longitudo in praematuro tantum varchar est (100), quod non occurrit necessitates hodiernae Oportet ager longitudo ad varchar aucta (255). Si manually unum temperaveris, centeni tabulae erunt, quae tempus edax est.

consilium

Mutare DDL propositiones quae hunc agrum faciunt in his tabulis requiri

  1. SELECT
  2. concat("ALTER TABLE `",table_name,"` MODIFY COLUMN `phone_name` varchar(255) NOT NULL COMMENT '手机名称';")
  3. FROM information_schema.columns
  4. WHERE
  5. table_schema = 'db_lingyejun' and column_name='phone_name' and character_maximum_length < 255 and is_nullable = 'NO';

Mutare DDL constitutiones, quae hunc agrum nullum in his tabulis faciunt

  1. SELECT
  2. concat("ALTER TABLE `",table_name,"` MODIFY COLUMN `phone_name` varchar(255) DEFULT NULL COMMENT '手机名称';")
  3. FROM information_schema.columns
  4. WHERE
  5. table_schema = 'db_lingyejun' and column_name='phone_name' and character_maximum_length < 255 and is_nullable = 'YES';

Si hic articulus te adiuvat, da "Ling Yejun" simile, gratias pro auxilio tuo.

Prima pagina:https://www.cnblogs.com/lingyejun/p/18293068