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CQL: Aggregation - Average
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Constraint Query Language A high level interface to SQL databases
library(cql/cql): CQL - Constraint Query Language
CQL Examples
CQL Simple INSERT
CQL Simple INSERT with retrieval of identity of the inserted
CQL Simple DELETE
CQL Simple SELECT
CQL Simple UPDATE
CQL WHERE with arithmetic comparison
CQL Simple INNER JOIN
CQL Arithmetic UPDATE with an INNER JOIN and a WHERE restriction
CQL: Confirm row does not exist
CQL: Aggregation - Count
CQL: Aggregation - Sum
CQL: Aggregation - Average
CQL: Maximum Value
CQL: Minimum Value
CQL: Aggregation requiring GROUP BY
CQL: INNER JOIN with an aggregation sub-query where the sub-query is constrained by a shared variable from the main query
CQL: INNER JOIN in an aggregation sub-query
CQL: Negation
CQL: EXISTS
CQL: Left Outer Join
CQL: List-based Restrictions
CQL: Compile time in-list constraint
CQL: Disjunction resulting in OR in WHERE clause
CQL: Disjunction resulting in different joins (implemented as a SQL UNION)
CQL: Disjunction resulting in different SELECT attributes (implemented as separate ODBC queries)
CQL: ORDER BY
CQL: DISTINCT
CQL: SELECT with NOT NULL restriction
CQL: First N
CQL: Self JOIN
CQL: Removing null comparisions
CQL: Three table JOIN
CQL: Three table JOIN with NOLOCK locking hint
CQL: SELECT with LIKE
CQL: Writing exceptions directly to the database
CQL: TOP N is Parametric
CQL: Using compile_time_goal/1
CQL: ON
CQL: Expressions In Where Restrictions
CQL: Explicitly avoid the "No WHERE restriction" message
CQL: HAVING
CQL: INSERT and UPDATE value in-line formatting
CQL: Negations in WHERE Clauses
CQL: Predicate-generated Attribute Values
CQL: INSERT from SELECT
1.7.12
CQL: Aggregation - Average
{[], se_lt_x :: [avg(c)-C]}
Calculate the mean of the values of attribute c in table se_lt_x