Dilip Biswal
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c839d09789
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[SPARK-28773][DOC][SQL] Handling of NULL data in Spark SQL
### What changes were proposed in this pull request?
Document ```NULL``` semantics in SQL Reference Guide.
### Why are the changes needed?
Currently Spark lacks documentation on how `NULL` data is handled in various expressions and operators. This is aimed at addressing this issue.
### Does this PR introduce any user-facing change?
Yes.
**Before:**
There was no documentation for this.
**After.**
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### How was this patch tested?
Tested using jykyll build --serve
Closes #25726 from dilipbiswal/sql-ref-null-data.
Lead-authored-by: Dilip Biswal <dbiswal@us.ibm.com>
Co-authored-by: Xiao Li <gatorsmile@gmail.com>
Signed-off-by: Xiao Li <gatorsmile@gmail.com>
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2019-09-09 13:41:17 -07:00 |
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