22title : LEFT
33---
44
5- θΏεε符串 ` str ` δΈζε·¦θΎΉη ` len ` δΈͺε符οΌε¦ζδ»»δ½εζ°δΈΊ ` NULL ` οΌεθΏε ` NULL ` γ
5+ θΏεε符串 ` str ` ζε·¦θΎΉη ` len ` δΈͺε符οΌε¦ζδ»»δΈεζ°δΈΊ NULLοΌεθΏε NULLγε¦ζ ` len ` ε€§δΊ ` str ` ηιΏεΊ¦οΌεθΏεζ΄δΈͺ ` str ` γ
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77## θ―ζ³
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@@ -12,10 +12,10 @@ LEFT(<str>, <len>);
1212
1313## εζ°
1414
15- | εζ° | ζθΏ° |
16- | ----------- | --------------------------------------------------|
17- | ` <str> ` | δΈ»ε符串οΌδ»δΈζεε符 |
18- | ` <len> ` | ε符ζ°ι |
15+ | εζ° | ζθΏ° |
16+ | ----------| ---- --------------------------------------------------|
17+ | ` <str> ` | θ¦δ»δΈζεε符ηδΈ»ε符串 |
18+ | ` <len> ` | θ¦ζεηε符ζ°ι |
1919
2020## θΏεη±»ε
2121
@@ -24,10 +24,11 @@ LEFT(<str>, <len>);
2424## η€ΊδΎ
2525
2626``` sql
27- SELECT LEFT(' foobarbar' , 5 );
28- + -- --------------------+
29- | LEFT(' foobarbar' , 5 ) |
30- + -- --------------------+
31- | fooba |
32- + -- --------------------+
27+ SELECT LEFT(' foobarbar' , 5 ), LEFT(' foobarbar' , 10 );
28+
29+ ββββββββββββββββββββββββββββββββββββββββββββββββ
30+ β left(' foobarbar' , 5 ) β left(' foobarbar' , 10 ) β
31+ ββββββββββββββββββββββββΌββββββββββββββββββββββββ€
32+ β fooba β foobarbar β
33+ ββββββββββββββββββββββββββββββββββββββββββββββββ
3334```
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