์ „์ฒด ๊ธ€ 403

[DB] SQL ๊ตฌ๋ฌธ์˜ ์ข…๋ฅ˜

1. DDL( Data Definition Language ) -๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค๋‚˜ ํ…Œ์ด๋ธ” ๋“ฑ์„ ์ƒ์„ฑ, ๋ณ€๊ฒฝ, ์‚ญ์ œ -CREATE, ALTER, RENAME, TRUNCATE, DROP 2. DML( Data Manipulation Language ) -๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค์— ์ €์žฅ๋œ ๋ฐ์ดํ„ฐ๋ฅผ ์ฒ˜๋ฆฌํ•˜๊ฑฐ๋‚˜ ์กฐํšŒ, ๊ฒ€์ƒ‰ -SELECT, INSERT, UPDATE, DELETE 3. DCL( Data Control Language ) -ํŠน์ • ์‚ฌ์šฉ์ž์—๊ฒŒ ๊ถŒํ•œ์„ ๋ถ€์—ฌํ•˜๊ฑฐ๋‚˜ ์ œ๊ฑฐ -GRANT, REVOKE 4. TCL( Transaction Control Language ) -DML์— ์˜ํ•ด ๋ณ€๊ฒฝ๋œ ๋‚ด์šฉ์„ ๊ด€๋ฆฌ -COMMIT, ROLLBACK

DB_Study/DataBase 2021.03.03

[DB] Relational Database ( ๊ด€๊ณ„ํ˜• ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค )

โœ” RDB ( Relational Database ) -๊ด€๊ณ„ํ˜• ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค๋Š” ํ…Œ์ด๋ธ”๋กœ ์ด๋ฃจ์–ด์ ธ์žˆ์œผ๋ฉฐ ํ…Œ์ด๋ธ”์€ ํ‚ค(key)์™€ ๊ฐ’(value)์˜ ๊ด€๊ณ„๋ฅผ ๋‚˜ํƒ€๋ƒ„ -๋ฐ์ดํ„ฐ์˜ ์ข…์†์„ฑ์„ ๊ด€๊ณ„๋กœ ๋‚˜ํƒ€๋‚ธ๊ฒƒ์ด ํŠน์ง• -๊ฐ€์žฅ ๋งŽ์ด ์‚ฌ์šฉ๋˜๊ณ ์žˆ๋Š” ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค์˜ ํ•œ ์ข…๋ฅ˜ โœ” RDBMS ( Relational Database Management System ) -RDB๋ฅผ ๊ด€๋ฆฌํ•  ์ˆ˜ ์žˆ๋Š” ์†Œํ”„ํŠธ์›จ์–ด

DB_Study/DataBase 2021.03.03

[Java] java.lang.StringIndexOutOfBoundsException: String index out of range

java.lang.StringIndexOutOfBoundsException: String index out of range : 6 โœ” Solution String์˜ ์ธ๋ฑ์Šค์— ์ ‘๊ทผํ•˜๋Š”๊ณณ์„ ์ฒดํฌํ•œ๋‹ค ์˜ˆ) // testStr์˜ length๋Š” 5์ด๋ฉฐ ์ธ๋ฑ์Šค์˜ ๋ฒ”์œ„๋Š” 0~4๋‹ค String testStr = "ABCDE"; // testStr.substring(0, 6)์€ 0~5๋ฒˆ์งธ ์ธ๋ฑ์Šค๋ฅผ ์ ‘๊ทผํ•˜๊ธฐ๋•Œ๋ฌธ์— // ์ธ๋ฑ์Šค ์œ ํšจ๋ฒ”์œ„๋ฅผ ๋ฒ—์–ด๋‚˜ ์—๋Ÿฌ ๋ฐœ์ƒ String subStr = testStr.substring(0, 6);

Dev_Log 2021.03.02

[MyBatis] Request processing failed; nested exception is org.apache.ibatis.binding.BindingException: Invalid bound statement (not found)

๋ชจ๋“ ์„ธํŒ…์„ ๋‹คํ–ˆ๋Š”๋ฐ๋„ Mapper ๋ฐ”์ธ๋”ฉ์—๋Ÿฌ๊ฐ€ ๋ฐœ์ƒํ•˜๋Š”๊ฒฝ์šฐ Request processing failed; nested exception is org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): โœ” Solution Mapper ์ธํ„ฐํŽ˜์ด์Šค์˜ ํŒจํ‚ค์ง€๋ฅผ ๋‹ค๋ฅธ๊ณณ์œผ๋กœ ์˜ฎ๊ธดํ›„ ํ•ด๊ฒฐ( ์ดํด๋ฆฝ์Šค์˜ ๋ฌธ์ œ๋กœ ์ƒ๊ฐ๋จ )

Dev_Log 2021.02.26

[Java] java.lang.NoSuchMethodError:org.springframework.web.servlet.tags.HtmlEscapeTag.setDefaultHtmlEscape(Ljava/lang/String;)V

java.lang.NoSuchMethodError: org.springframework.web.servlet.tags.HtmlEscapeTag.setDefaultHtmlEscape(Ljava/lang/String;)V โœ” ํ•ด๋‹น ๋ฉ”์†Œ๋“œ๋ฅผ ์ฐพ์„ ์ˆ˜ ์—†์„๋•Œ ๋ฐœ์ƒ๋˜๋Š” ์—๋Ÿฌ spring-webmvc-4.3.9.RELEASE.jar์— ์ •์˜๋œ ๋ฉ”์†Œ๋“œ๋กœ ๋งค๊ฐœ๋ณ€์ˆ˜ํƒ€์ž…์€ boolean์ด์—ˆ๊ณ  jsp์—์„œ ๋กœ true๋ฅผ ์ „๋‹ฌ๋˜๋Š” ์ƒํ™ฉ์—์„œ ์—๋Ÿฌ๋ฐœ์ƒ โœ” Solution 1. WEB-INF/lib ์— ์žˆ๋Š” jarํŒŒ์ผ๊ณผ ๊ฐ™์€ ํŒŒ์ผ์ด java/jre/lib/ext ๊ฒฝ๋กœ ๋˜๋Š” apacheํด๋” ๋ฐ‘์— lib์— ์žˆ์–ด jarํŒŒ์ผ ์ค‘๋ณต์œผ๋กœ ์‹คํ–‰ํ•˜๋ ค๋Š” ๋ฉ”์†Œ๋“œ๋ฅผ ์–ด๋–ค๊ฒƒ์„ ์ฐธ์กฐํ• ์ง€ ๋ชจ๋ฅผ๋•Œ ๋ฐœ์ƒํ•˜๋Š” ๊ฒฝ์šฐ ํ•œ์ชฝ์˜ jar์„ ์‚ญ์ œํ•˜์—ฌ ํ•ด๊ฒฐํ•œ๋‹ค 2. ํ•ด๋‹น ํ•จ์ˆ˜..

Dev_Log 2021.02.26

[Eclipse] ์›นํ”„๋กœ์ ํŠธ import์‹œ JSPํŒŒ์ผ๋“ค์—์„œ javax.servlet.jsp.PageContext cannot be resolved to a type

์›นํ”„๋กœ์ ํŠธ import์‹œ JSPํŒŒ์ผ์—์„œ javax.servlet.jsp.PageContext cannot be resolved to a type ์—๋Ÿฌ ๋ฐœ์ƒ โœ” Solution - ํ•ด๋‹น ํ”„๋กœ์ ํŠธ ์šฐํด๋ฆญ -> Properties -> Project Facts ์—์„œ Runtimeํƒญ์— Apache Tomcat์— ์ฒดํฌ๊ฐ€ ๋˜์–ด์žˆ์ง€ ์•Š๋‹ค๋ฉด ์ฒดํฌํ›„ Apply

Dev_Log 2021.02.26