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MySQL中如何增加字段SQL語(yǔ)句

瀏覽:240日期:2023-02-18 16:43:31
目錄
  • MySQL增加字段SQL語(yǔ)句
  • MYSQL為多表批量新增字段
    • navicat中新建procedure
    • 新建查詢
  • 總結(jié)

    MySQL增加字段SQL語(yǔ)句

    使用ALTER TABLE向MySQL數(shù)據(jù)庫(kù)的表中添加字段

    -- 向buildBaseInfo中添加字段ALTER TABLE table_name ADD COLUMN column_name VARCHAR(100) DEFAULT NULL COMMENT "新加字段" AFTER old_column;

    語(yǔ)句內(nèi)容:

    • table_name:表明;
    • column_name:需要添加的字段名;
    • VARCHAR(100):字段類型為varchar,長(zhǎng)度100;
    • DEFAULT NULL:默認(rèn)值NULL;
    • AFTER old_column:新增字段添加在old_column字段后面。

    MYSQL為多表批量新增字段

    navicat中新建procedure

    CREATE DEFINER=`portal`@`%` PROCEDURE `pro_AddColumn`(	IN tab VARCHAR(100))BEGINIF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name=tab AND COLUMN_NAME="CREATE_DATE") THENSET @exe = CONCAT("ALTER TABLE ",tab," ADD CREATE_DATE DATE COMMENT "創(chuàng)建時(shí)間"");PREPARE sql1 FROM @exe;EXECUTE sql1;END IF;IF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name=tab AND COLUMN_NAME="CREATE_USER") THENSET @exe = CONCAT("ALTER TABLE ",tab," ADD CREATE_USER VARCHAR(50) COMMENT "創(chuàng)建人"");PREPARE sql1 FROM @exe;EXECUTE sql1;END IF;IF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name=tab AND COLUMN_NAME="MODIFIED_DATE") THENSET @exe = CONCAT("ALTER TABLE ",tab," ADD MODIFIED_DATE DATE COMMENT "修改時(shí)間"");PREPARE sql1 FROM @exe;EXECUTE sql1;END IF;IF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name=tab AND COLUMN_NAME="MODIFIED_USER") THENSET @exe = CONCAT("ALTER TABLE ",tab," ADD MODIFIED_USER VARCHAR(50) COMMENT "修改人"");PREPARE sql1 FROM @exe;EXECUTE sql1;END IF;IF NOT EXISTS(SELECT 1 FROM information_schema.columns WHERE table_name=tab AND COLUMN_NAME="IP") THENSET @exe = CONCAT("ALTER TABLE ",tab," ADD IP VARCHAR(40) COMMENT "ip"");PREPARE sql1 FROM @exe;EXECUTE sql1;END IF;END

    把代碼復(fù)制進(jìn)去,保存

    新建查詢

    CALL pro_AddColumn("tableA");CALL pro_AddColumn("tableB");CALL pro_AddColumn("tableC");CALL pro_AddColumn("tableD");

    代碼復(fù)制進(jìn)去執(zhí)行即可,括號(hào)里面是表名

    總結(jié)

    以上為個(gè)人經(jīng)驗(yàn),希望能給大家一個(gè)參考,也希望大家多多支持。

    標(biāo)簽: MySQL
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