SQL: Implement IFNULL variant of COALESCE #35762
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IFNULL is a MySQL variant (also used in other DBs) which takes only 2 arguments and returns the first one that is not null. Closes: elastic#35749
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Pinging @elastic/es-search |
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| ["source","sql",subs="attributes,callouts,macros"] | ||
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| include-tagged::{sql-specs}/docs.csv-spec[ifNullReturnSecond] |
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I think here you meant ifNullReturnFirst.
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Oh, Thx, stupid copy paste...
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| import java.util.List; | ||
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| public class IFNull extends Coalesce { |
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Wondering if the class name shouldn't be IfNull...
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I choose IFNull so that the function is not registered as IF_NULL, because then we would need an alias IFNULL on top.
| @@ -31,7 +31,7 @@ public Coalesce(Location location, List<Expression> fields) { | |||
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| @Override | |||
| protected NodeInfo<Coalesce> info() { | |||
| protected NodeInfo<? extends ConditionalFunction> info() { | |||
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If IFNULL won't work, use ? extends Coalesce.
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| import java.util.List; | ||
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| public class IFNull extends Coalesce { |
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| public class IFNull extends Coalesce { | ||
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| public IFNull(Location location, List<Expression> fields) { |
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Since IfNull always expects 2 arguments, force this into the constructor:
public IfNull(Location location, Expression left, Expression right) {
super(location, asList(left, right));
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| @Override | ||
| protected Pipe makePipe() { | ||
| if (children().size() != 2) { |
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If the constructor is modified, this method won't be needed anymore.
IFNULL is a MySQL variant (also used in other DBs) which takes only 2 arguments and returns the first one that is not null. Closes: #35749
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Backported to |
IFNULL is a MySQL variant (also used in other DBs) which
takes only 2 arguments and returns the first one that is not null.
Closes: #35749