filter\_by\_string(table\_name=None, view\_name='', expression=None, mode=None, column\_names=None, options={"{"}{"}"})\[source]

Calculates which objects from a table or view match a string expression for the given string columns. Setting case\_sensitive can modify case sensitivity in matching for all modes except search. For search mode details and limitations, see Full Text Search.

Parameters

table\_name (str) –

Name of the table on which the filter operation will be performed, in \[schema\_name.]table\_name format, using standard name resolution rules. Must be an existing table or view.

view\_name (str) –

If provided, then this will be the name of the view containing the results, in \[schema\_name.]view\_name format, using standard name resolution rules and meeting table naming criteria. Must not be an already existing table or view. The default value is ‘’.

expression (str) –

The expression with which to filter the table.

mode (str) –

The string filtering mode to apply. See below for details. Allowed values are:

search – Full text search query with wildcards and boolean operators. Note that for this mode, no column can be specified in input parameter column\_names; all string columns of the table that have text search enabled will be searched.
equals – Exact whole-string match (accelerated).
contains – Partial substring match (not accelerated). If the column is a string type (non-charN) and the number of records is too large, it will return 0.
starts\_with – Strings that start with the given expression (not accelerated). If the column is a string type (non-charN) and the number of records is too large, it will return 0.
regex – Full regular expression search (not accelerated). If the column is a string type (non-charN) and the number of records is too large, it will return 0.
search\_stats – Cross-shard BM25 corpus statistics for one (column, query) pair. Returns the merged BM25 statistics (max\_doc, doc\_count, sum\_total\_term\_freq, per-term doc\_freq / total\_term\_freq) needed by callers that score documents themselves (e.g. text\_match\_bm25\_global SQL function pre-pass). Requires column\_names to contain exactly one column with text search enabled. The view\_name field is ignored — this mode does not produce a result table.

column\_names (list of str) –

List of columns on which to apply the filter. Ignored for search mode. The user can provide a single element (which will be automatically promoted to a list internally) or a list.

options (dict of str to str) –

Optional parameters. Allowed keys are:

create\_temp\_table – If true, a unique temporary table name will be generated in the sys\_temp schema and used in place of input parameter view\_name. This is always allowed even if the caller does not have permission to create tables. The generated name is returned in qualified\_view\_name. Allowed values are:
- true
- false
The default value is ‘false’.
collection\_name – \[DEPRECATED–please specify the containing schema for the view as part of input parameter view\_name and use GPUdb.create\_schema() to create the schema if non-existent] Name of a schema for the newly created view. If the schema is non-existent, it will be automatically created.
case\_sensitive – If false then string filtering will ignore case. Does not apply to search mode. Allowed values are:
- true
- false
The default value is ‘true’.

The default value is an empty dict ( {"{"}{"}"} ).

Returns

A dict with the following entries–

count (long) –

The number of records that passed the string filter.

info (dict of str to str) –

Additional information. Allowed keys are:

qualified\_view\_name – The fully qualified name of the view (i.e. including the schema).

The default value is an empty dict ( {"{"}{"}"} ).

stats\_data (bytes) –

Serialized cross-shard BM25 corpus statistics, populated for search\_stats mode and empty otherwise. Wire format matches the merged BM25GlobalStats blob the BM25 stats worker produces internally (max\_doc, doc\_count, sum\_total\_term\_freq, sum\_doc\_freq, num\_terms, then per term: term, doc\_freq, total\_term\_freq). Clients that consume this perform their own scoring; the gpudb client library will expose a parser as a future convenience. The default value is ‘’.