and including 1.5. This bug was fixed in v.1.5.1. From that version onward, such a statement will yield an empty result set. 3.2. Boolean operations All the operators examined so far return NULL if any exactly 1 row; • false if the search condition is true for more than 1 row. Whether the other rows yield false, NULL or a combination thereof, is irrelevant. NOT SINGULAR will always return the opposite integer type, AVG is always rounded towards 0. For instance, 6 non-null INT records with a sum of -11 yield an average of -1, not -2. [2] LIST was added in Firebird 2.1 Chapter 8. Aggregate functions 28

the brackets [ ] are meant to appear literally.) Each subscript is itself an expression, which must yield an integer value. In general the array expression must be parenthesized, but the parentheses may aggregate expression invokes the aggregate across all input rows for which the given expression(s) yield non-null values. (Actually, it is up to the aggregate function whether to ignore null values or not inconsistent behavior exhibited by PostgreSQL versions prior to 8.2. The ordinary comparison operators yield null (signifying “unknown”) when either input is null. Another way to do comparisons is with the IS

the brackets [ ] are meant to appear literally.) Each subscript is itself an expression, which must yield an integer value. In general the array expression must be parenthesized, but the parentheses may aggregate expression invokes the aggregate across all input rows for which the given expression(s) yield non-null values. (Actually, it is up to the aggregate function whether to ignore null values or not inconsistent behavior exhibited by PostgreSQL versions prior to 8.2. The ordinary comparison operators yield null (signifying “unknown”) when either input is null. Another way to do comparisons is with the IS

have to fall back to individual inserts in order to implement the above algorithm 42 for rows that yield dup keys. For simplicity, we may not do bulk insert in the initial implementation. ### What won’t • A table can have multiple Vindexes. • Vindexes can be NonUnique, which allows a column value to yield multiple keyspace IDs. • Vindexes can be a simple function or be based on a lookup table. • Vindexes non-unique index. It is a secondary index for searching by an alternate WHERE clause. An input value could yield multiple keyspace IDs, and rows could be matched from multiple shards. For example, if a table has

the brackets [ ] are meant to appear literally.) Each subscript is itself an expression, which must yield an integer value. In general the array expression must be parenthesized, but the parentheses can Most aggregate functions ignore null inputs, so that rows in which one or more of the expression(s) yield null are discarded. This can be assumed to be true, unless otherwise specified, for all built-in aggregates elements in an array across all dimensions. It is effectively the number of rows a call to unnest would yield: SELECT cardinality(schedule) FROM sal_emp WHERE name = ’Carol’; cardinality ------------- 4 (1

the brackets [ ] are meant to appear literally.) Each subscript is itself an expression, which must yield an integer value. In general the array expression must be parenthesized, but the parentheses can Most aggregate functions ignore null inputs, so that rows in which one or more of the expression(s) yield null are discarded. This can be assumed to be true, unless otherwise specified, for all built-in aggregates elements in an array across all dimensions. It is effectively the number of rows a call to unnest would yield: SELECT cardinality(schedule) FROM sal_emp WHERE name = ’Carol’; cardinality ------------- 4 (1

Most aggregate functions ignore null inputs, so that rows in which one or more of the expression(s) yield null are discarded. This can be assumed to be true, unless otherwise specified, for all built-in aggregates will be an array of the same type but one higher dimension; in this case all the subquery rows must yield arrays of identical dimensionality, else the result would not be rectangular. The subscripts of an monetary amounts and other quantities where exactness is required. Calculations with numeric values yield exact results where possible, e.g., addition, subtraction, multiplication. However, calculations on

Most aggregate functions ignore null inputs, so that rows in which one or more of the expression(s) yield null are discarded. This can be assumed to be true, unless otherwise specified, for all built-in aggregates will be an array of the same type but one higher dimension; in this case all the subquery rows must yield arrays of identical dimensionality, else the result would not be rectangular. The subscripts of an monetary amounts and other quantities where exactness is required. Calculations with numeric values yield exact results where possible, e.g., addition, subtraction, multiplication. However, calculations on

the brackets [ ] are meant to appear literally.) Each subscript is itself an expression, which must yield an integer value. In general the array expression must be parenthesized, but the parentheses can aggregate expression invokes the aggregate across all input rows for which the given expression(s) yield non-null values. (Actually, it is up to the aggregate function whether to ignore null values or not inconsistent behavior exhibited by PostgreSQL versions prior to 8.2. The ordinary comparison operators yield null (signifying “unknown”) when either input is null. Another way to do comparisons is with the IS

the brackets [ ] are meant to appear literally.) Each subscript is itself an expression, which must yield an integer value. In general the array expression must be parenthesized, but the parentheses can aggregate expression invokes the aggregate across all input rows for which the given expression(s) yield non-null values. (Actually, it is up to the aggregate function whether to ignore null values or not inconsistent behavior exhibited by PostgreSQL versions prior to 8.2. The ordinary comparison operators yield null (signifying “unknown”) when either input is null. An- other way to do comparisons is with the