inflearn logo
Khóa học

Khóa học
Chia sẻ kiến thức

Bài viết của hoon

hoon hoon

@chlxogns928264

Số lượng đánh giá đã viết
17
Xếp hạng trung bình
5.0

Bài viết 11

Hỏi & Đáp

(1,2강) char, varchar, text 관련 질문

MySQL 서버에 연결된 컨넥션중에서 해당 테이블을 사용하는 컨넥션의 개수만큼 해당 메모리 공간 예약이 필요합니다. 그렇군요 😃 내부적으로 테이블을 리빌드하며, 온라인으로 컬럼 추가가 불가능합니다. default를 표현식으로 추가하는 경우는 instant로 컬럼추가가 불가능하군요. 신기하네요. TEXT 타입은 항상 오프페이지로 저장되는 것은 아닙니다. 하나의 레코드 사이즈가 데이터페이지의 절반 크기보다 작은 경우 가변길이 컬럼의 값은 기존 다른 컬럼들과 함께 동일한 데이터페이지에 저장됩니다. text는 왜 row사이즈 제한(64KB)에 포함안되는지는 잘 이해가 안되네요. text나 varchar 둘다 오프페이지로도 저장될 수 있고 저장될 수 있어서 비슷한거같은데.. https://dev.mysql.com/doc/refman/8.0/en/column-count-limit.html#row-size-limits 공식문서에도 이유는 안나와있군요 🤔 근데 프로그램이 다 이유가 있는 동작만 하는건 아니니 그냥 그러려니.. 답변 감사합니다. 좀더 찾아보니 성욱님이 적으신 블로그글에 제 질문과 관련된 내용들이 많이 나오네요. https://medium.com/daangn/varchar-vs-text-230a718a22a1

Lượt thích
0
Số bình luận
4
Lượt xem
630

Hỏi & Đáp

(1,2강) char, varchar, text 관련 질문

5번은 https://www.inflearn.com/questions/1305027/text-%ED%83%80%EC%9E%85-%EB%8D%B0%EC%9D%B4%ED%84%B0%EA%B0%80-%EC%A0%80%EC%9E%A5%EB%90%98%EB%8A%94-%EC%9C%84%EC%B9%98%EC%97%90-%EB%8C%80%ED%95%B4-%EC%A7%88%EB%AC%B8%EB%93%9C%EB%A6%BD%EB%8B%88%EB%8B%A4 여기에 질문이 있군요.

Lượt thích
0
Số bình luận
4
Lượt xem
630

Hỏi & Đáp

배포해서 서버접속하는것까지 성공하였습니다

spring: config: activate: on-profile: local datasource: url: "jdbc:h2:mem:balance;MODE=MYSQL;NON_KEYWORDS=USER" username: "sa" password: "" driver-class-name: org.h2.Driver jpa: hibernate: ddl-auto: create properties: hibernate: format_sql: true show_sql: true dialect: org.hibernate.dialect.H2Dialect open-in-view: false h2: console: enabled: true path: /h2-console server: port: 8081 --- spring: config: activate: on-profile: dev datasource: url: "jdbc:mysql://localhost/balance" username: "root" password: "Abcd1234!" driver-class-name: com.mysql.cj.jdbc.Driver jpa: hibernate: ddl-auto: none properties: hibernate: format_sql: true show_sql: true dialect: org.hibernate.dialect.MySQL8Dialect open-in-view: false server: port: 8081 와 같고 dev 로 실행시켰고 mysql 안에 balance 에는 테이블과 정보를 새로 넣어두었습니다

Lượt thích
1
Số bình luận
2
Lượt xem
383

Hỏi & Đáp

프로젝트 실행이 안돼요

dependencies { implementation 'org.springframework.boot:spring-boot-starter-web' } 를 추가하였더니 정상작동합니다 이유가 뭔가요????

Lượt thích
0
Số bình luận
3
Lượt xem
869

Hỏi & Đáp

프로젝트 실행이 안돼요

/Library/Java/JavaVirtualMachines/jdk-11.jdk/Contents/Home/bin/java -javaagent:/Applications/IntelliJ IDEA CE.app/Contents/lib/idea_rt.jar=63069:/Applications/IntelliJ IDEA CE.app/Contents/bin -Dfile.encoding=UTF-8 -classpath /Users/kimyunsoo/Downloads/jdbc 7/out/production/classes:/Users/kimyunsoo/Downloads/jdbc 7/out/production/resources:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot-starter-jdbc/2.7.5/b57c3f8fb2fe235a8ff368755092371423bbc5b3/spring-boot-starter-jdbc-2.7.5.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot-starter/2.7.5/c28e1546461803490588085345ba5d2897d232bc/spring-boot-starter-2.7.5.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/com.zaxxer/HikariCP/4.0.3/107cbdf0db6780a065f895ae9d8fbf3bb0e1c21f/HikariCP-4.0.3.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework/spring-jdbc/5.3.23/c859919a644942822e49cb7f2404b2c4d3cba040/spring-jdbc-5.3.23.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot-autoconfigure/2.7.5/96646e63a2296d0a3209383e81cdb8c87ab2f913/spring-boot-autoconfigure-2.7.5.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot/2.7.5/fd04e228e6e21b7ad13c10ae29afd31868d842e5/spring-boot-2.7.5.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot-starter-logging/2.7.5/61f4c53e35baa31a269bbeb7bb9d5e781448feef/spring-boot-starter-logging-2.7.5.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/jakarta.annotation/jakarta.annotation-api/1.3.5/59eb84ee0d616332ff44aba065f3888cf002cd2d/jakarta.annotation-api-1.3.5.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework/spring-core/5.3.23/91407dc1106ea423c44150f3da1a0b4f8e25e5ca/spring-core-5.3.23.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.yaml/snakeyaml/1.30/8fde7fe2586328ac3c68db92045e1c8759125000/snakeyaml-1.30.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.slf4j/slf4j-api/1.7.36/6c62681a2f655b49963a5983b8b0950a6120ae14/slf4j-api-1.7.36.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework/spring-tx/5.3.23/ab313b4028c62e18fe02defdd5050af704778428/spring-tx-5.3.23.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework/spring-beans/5.3.23/3bdefbf6042ed742cbe16f27d2d14cca9096a606/spring-beans-5.3.23.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework/spring-context/5.3.23/530b36b2ce2c9e471c6a260c3f181bcd20325a58/spring-context-5.3.23.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/ch.qos.logback/logback-classic/1.2.11/4741689214e9d1e8408b206506cbe76d1c6a7d60/logback-classic-1.2.11.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-to-slf4j/2.17.2/17dd0fae2747d9a28c67bc9534108823d2376b46/log4j-to-slf4j-2.17.2.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.slf4j/jul-to-slf4j/1.7.36/ed46d81cef9c412a88caef405b58f93a678ff2ca/jul-to-slf4j-1.7.36.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework/spring-jcl/5.3.23/3c7eb5fcca67b611065f73ff4325e398f8b051a3/spring-jcl-5.3.23.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework/spring-aop/5.3.23/30d0034ba29178e98781d85f51a7eb709a628e9b/spring-aop-5.3.23.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.springframework/spring-expression/5.3.23/3a676bf4b9bc42bd37ab5ad264acb6ceb63397a2/spring-expression-5.3.23.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/ch.qos.logback/logback-core/1.2.11/a01230df5ca5c34540cdaa3ad5efb012f1f1f792/logback-core-1.2.11.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-api/2.17.2/f42d6afa111b4dec5d2aea0fe2197240749a4ea6/log4j-api-2.17.2.jar:/Users/kimyunsoo/.gradle/caches/modules-2/files-2.1/com.h2database/h2/2.1.214/d5c2005c9e3279201e12d4776c948578b16bf8b2/h2-2.1.214.jar hello.jdbc.JdbcApplication . ____ _ /\\ / ___'_ __ ( _)_ _ \ \ \ \ ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/ ___)| |_)| | | | | || (_| | ) ) ) ) ' |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: (v2.7.5) 2023-08-04 11:11:53.900 INFO 59660 --- [ main] hello.jdbc.JdbcApplication : Starting JdbcApplication using Java 11.0.18 on gim-yeonsuui-MacBookAir.local with PID 59660 (/Users/kimyunsoo/Downloads/jdbc 7/out/production/classes started by kimyunsoo in /Users/kimyunsoo/Downloads/jdbc 7) 2023-08-04 11:11:53.903 INFO 59660 --- [ main] hello.jdbc.JdbcApplication : No active profile set, falling back to 1 default profile: "default" 2023-08-04 11:11:54.570 INFO 59660 --- [ main] hello.jdbc.JdbcApplication : Started JdbcApplication in 0.908 seconds (JVM running for 1.132) Process finished with exit code 0 이렇게 뜨고 바로 꺼집니다 ㅠㅠ

Lượt thích
0
Số bình luận
3
Lượt xem
869