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31 lines
772 B
Text
31 lines
772 B
Text
[[esql-substring]]
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=== `SUBSTRING`
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Returns a substring of a string, specified by a start position and an optional
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length. This example returns the first three characters of every last name:
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[source,esql]
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----
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FROM employees
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| KEEP last_name
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| EVAL ln_sub = SUBSTRING(last_name, 1, 3)
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----
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A negative start position is interpreted as being relative to the end of the
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string. This example returns the last three characters of of every last name:
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[source,esql]
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----
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FROM employees
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| KEEP last_name
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| EVAL ln_sub = SUBSTRING(last_name, -3, 3)
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----
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If length is omitted, substring returns the remainder of the string. This
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example returns all characters except for the first:
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[source,esql]
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----
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FROM employees
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| KEEP last_name
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| EVAL ln_sub = SUBSTRING(last_name, 2)
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----
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