Results of 1 - 10 of about 17 for comparisons (0.002 sec.)
- Subqueries 13001
- Subqueries are parenthesized query expressions that appear as part of a larger, outer query. Subqueries are usually based on SELECT ... FROM , but in DuckDB other query constructs such as PIVOT can also appear as a subquery. Scalar Subquery
...RRAY to collect all results in a list. SELECT ARRAY(SELECT grade FROM grades) AS all_grades; all_grades [7, 9, 8] Subquery Comparisons: ALL , ANY and SOME In the section on scalar subqueries , a scalar expression was compared directly to a subquery using th...e equality comparison operator ( = ). Such direct comparisons only make sense with scalar subqueries. Scalar expressions can still be compared to single-column subqueries returning mul...ellent; returns excellent false because 8 is not greater than or equal to the subquery result 9. And thus, because not all comparisons evaluate to true , >= ALL as a whole evaluates to false . ANY The ANY quantifier specifies that the comparison as a whole... - https://man.mtool.work/duckdb/2.0/sql/expressions/subqueries.html
- List Type 11794
- A LIST column encodes lists of values. Fields in the column can have values with different lengths, but they must all have the same underlying type. LIST s are typically used to store arrays of numbers, but can contain any uniform data type
...', 'c'], 2, 3) ['b', 'c'] Comparison and Ordering The LIST type can be compared using all the comparison operators . These comparisons can be used in logical expressions such as WHERE and HAVING clauses, and return BOOLEAN values . The LIST ordering is defi...s are equal, then the longer list sorts last. NULL values are compared following PostgreSQL's semantics: At the top level, comparisons to NULL yield NULL ; At lower nesting levels NULL s are greater than other values. Here are some queries returning true fo... - https://man.mtool.work/duckdb/2.0/sql/data_types/list.html
- Collations 10569
- Collations provide rules for how text should be sorted or compared in the execution engine. Collations are useful for localization, as the rules for how text should be ordered are different for different languages or for different countries
...s not make much sense for special unicode characters. It is, however, by far the fastest method of performing ordering and comparisons. Hence it is recommended to stick with the BINARY collation unless required otherwise. The BINARY collation is also availa...The NOACCENT collation compares characters as equal regardless of their accents. The NFC collation performs NFC-normalized comparisons, see Unicode normalization for more information. SELECT 'hello' = 'hElLO'; false SELECT 'hello' COLLATE NOCASE = 'hElLO';... - https://man.mtool.work/duckdb/2.0/sql/expressions/collations.html
- Boolean Type 9759
- Name Aliases Description BOOLEAN BOOL Logical Boolean ( true / false ) The BOOLEAN type represents a statement of truth (“true” or “false”). In SQL, the BOOLEAN field can also have a third state “unknown” which is represented by the SQL NUL
...n values can be explicitly created using the literals true and false . However, they are most often created as a result of comparisons or conjunctions. For example, the comparison i > 10 results in a Boolean value. Boolean values can be used in the WHERE an... - https://man.mtool.work/duckdb/2.0/sql/data_types/boolean.html
- Struct Data Type 8948
- Conceptually, a STRUCT column contains an ordered list of columns called “entries”. The entries are referenced by name using strings. This document refers to those entry names as keys. Each row in the STRUCT column must have the same keys.
...SELECT {'x': 42} AS a); Comparison and Ordering The STRUCT type can be compared using all the comparison operators . These comparisons can be used in logical expressions such as WHERE and HAVING clauses, and return BOOLEAN values . Comparisons are done in l... - https://man.mtool.work/duckdb/2.0/sql/data_types/struct.html
- Comparisons 8948
- Comparison Operators The table below shows the standard comparison operators. Whenever either of the input arguments is NULL , the output of the comparison is NULL . Operator Description Example Result < less than 2 < 3 true > greater than
...) An explicit collation on any input to BETWEEN applies to the entire BETWEEN expression. This can differ from writing the comparisons separately, where the explicit collation applies only to the comparison that contains it: SELECT 'B' NOT BETWEEN ('A' COLL... - https://man.mtool.work/duckdb/2.0/sql/expressions/comparison_operators.html
- Map Type 8535
- MAP s are similar to STRUCT s in that they are an ordered list of key-value pairs. However, MAP s do not need to have the same keys present for each row, and thus are suitable for use cases where the schema is unknown beforehand or varies p
...: 5, 'key2': 43}, 'key3'); [] Comparison Operators Nested types can be compared using all the comparison operators . These comparisons can be used in logical expressions for both WHERE and HAVING clauses, as well as for creating Boolean values . The orderin... - https://man.mtool.work/duckdb/2.0/sql/data_types/map.html
- Result Verification 8138
- The standard way of verifying results of queries is using the query statement, followed by the letter I times the number of columns that are expected in the result. After the query, four dashes ( ---- ) are expected followed by the result v
...tting Values Besides direct result verification, the sqllogic test suite also has the option of using MD5 hashes for value comparisons. A test using hashes for result verification looks like this: query I SELECT g, string_agg(x,',') FROM strings GROUP BY g... - https://man.mtool.work/duckdb/2.0/dev/sqllogictest/result_verification.html
- SQL on Apache Arrow 8138
- DuckDB can query multiple different types of Apache Arrow objects. DuckDB pushes the filters of a query that it can translate, such as comparisons, into the scan of an Arrow dataset. Arrow tables, record batches, scanners and RecordBatchRea
... - https://man.mtool.work/duckdb/2.0/guides/python/sql_on_arrow.html
- Execution Format 8138
- Vector is the container format used to store in-memory data during execution. DataChunk is a collection of Vectors, used for instance to represent a column list in a PhysicalProjection operator. Data Flow DuckDB uses a vectorized query exec
...ut the functions to avoid having to call strlen and having to continuously check for null-pointers. The prefix is used for comparisons as an early out (when the prefix does not match, we know the strings are not equal and don't need to chase any pointers).... - https://man.mtool.work/duckdb/2.0/internals/vector.html
DuckDB 2.0 Documentation / man.mtool.work