Sha1Agg

Table of Contents



Returns a single SHA-1 hash of all of the values in each group, as a lower case hex string. Useful for detecting changes to a set of documents.

String Sha1Agg(AggregationArray valuesArray)

Ordering

The values are sorted before they are hashed, so the result does not depend on the order in which documents are read. Two groups with the same values produce the same hash.


round-pushpin Hashes the words of each language.
SELECT LanguageId, Sha1Agg(Text) as Hash FROM WordList:Word GROUP BY LanguageId




SQL :: Max
Returns the largest numeric value in each group. Use MaxString for text.
SQL :: MaxString
Returns the alphabetically largest value in each group.
SQL :: Mean
Returns the arithmetic mean of the values in each group (the same as Avg).
SQL :: Median
Returns the median (middle) value in each group. For an even number of values it is the average of the two middle values.
SQL :: Min
Returns the smallest numeric value in each group. Use MinString for text.
SQL :: MinString
Returns the alphabetically smallest value in each group.
SQL :: Mode
Returns the value that occurs most often in each group. When several values are tied, the first one encountered is returned.
SQL :: Order By
Order by sorts a result set by a given set of fields or expressions.
SQL :: Select
Select statements are used to read (or query) data from the database.
SQL :: Sha256Agg
Returns a single SHA-256 hash of all of the values in each group, as a lower case hex string. Useful for detecting changes to a set of documents.