Module: Sequel::Postgres::DatasetMethods
- Included in:
- JDBC::Postgres::Dataset, Dataset
- Defined in:
- lib/sequel/adapters/shared/postgres.rb
Overview
Instance methods for datasets that connect to a PostgreSQL database.
Defined Under Namespace
Modules: PreparedStatementMethods
Constant Summary collapse
- ACCESS_SHARE =
'ACCESS SHARE'.freeze
- ACCESS_EXCLUSIVE =
'ACCESS EXCLUSIVE'.freeze
- BOOL_FALSE =
'false'.freeze
- BOOL_TRUE =
'true'.freeze
- COMMA_SEPARATOR =
', '.freeze
- DELETE_CLAUSE_METHODS =
Dataset.clause_methods(:delete, %w'delete from using where returning')
- DELETE_CLAUSE_METHODS_91 =
Dataset.clause_methods(:delete, %w'with delete from using where returning')
- EXCLUSIVE =
'EXCLUSIVE'.freeze
- EXPLAIN =
'EXPLAIN '.freeze
- EXPLAIN_ANALYZE =
'EXPLAIN ANALYZE '.freeze
- FOR_SHARE =
' FOR SHARE'.freeze
- INSERT_CLAUSE_METHODS =
Dataset.clause_methods(:insert, %w'insert into columns values returning')
- INSERT_CLAUSE_METHODS_91 =
Dataset.clause_methods(:insert, %w'with insert into columns values returning')
- LOCK =
'LOCK TABLE %s IN %s MODE'.freeze
- NULL =
LiteralString.new('NULL').freeze
- PG_TIMESTAMP_FORMAT =
"TIMESTAMP '%Y-%m-%d %H:%M:%S".freeze
- QUERY_PLAN =
'QUERY PLAN'.to_sym
- ROW_EXCLUSIVE =
'ROW EXCLUSIVE'.freeze
- ROW_SHARE =
'ROW SHARE'.freeze
- SELECT_CLAUSE_METHODS =
Dataset.clause_methods(:select, %w'select distinct columns from join where group having compounds order limit lock')
- SELECT_CLAUSE_METHODS_84 =
Dataset.clause_methods(:select, %w'with select distinct columns from join where group having window compounds order limit lock')
- SHARE =
'SHARE'.freeze
- SHARE_ROW_EXCLUSIVE =
'SHARE ROW EXCLUSIVE'.freeze
- SHARE_UPDATE_EXCLUSIVE =
'SHARE UPDATE EXCLUSIVE'.freeze
- SQL_WITH_RECURSIVE =
"WITH RECURSIVE ".freeze
- UPDATE_CLAUSE_METHODS =
Dataset.clause_methods(:update, %w'update table set from where returning')
- UPDATE_CLAUSE_METHODS_91 =
Dataset.clause_methods(:update, %w'with update table set from where returning')
- SPACE =
Dataset::SPACE
- FROM =
Dataset::FROM
- APOS =
Dataset::APOS
- APOS_RE =
Dataset::APOS_RE
- DOUBLE_APOS =
Dataset::DOUBLE_APOS
- PAREN_OPEN =
Dataset::PAREN_OPEN
- PAREN_CLOSE =
Dataset::PAREN_CLOSE
- COMMA =
Dataset::COMMA
- AS =
Dataset::AS
- XOR_OP =
' # '.freeze
- CRLF =
"\r\n".freeze
- BLOB_RE =
/[\000-\037\047\134\177-\377]/n.freeze
- WINDOW =
" WINDOW ".freeze
- EMPTY_STRING =
''.freeze
Instance Method Summary collapse
-
#analyze ⇒ Object
Return the results of an EXPLAIN ANALYZE query as a string.
-
#complex_expression_sql_append(sql, op, args) ⇒ Object
Handle converting the ruby xor operator (^) into the PostgreSQL xor operator (#).
-
#explain(opts = {}) ⇒ Object
Return the results of an EXPLAIN query as a string.
-
#for_share ⇒ Object
Return a cloned dataset which will use FOR SHARE to lock returned rows.
-
#full_text_search(cols, terms, opts = {}) ⇒ Object
PostgreSQL specific full text search syntax, using tsearch2 (included in 8.3 by default, and available for earlier versions as an add-on).
-
#insert(*values) ⇒ Object
Insert given values into the database.
-
#insert_select(*values) ⇒ Object
Insert a record returning the record inserted.
-
#lock(mode, opts = {}) ⇒ Object
Locks all tables in the dataset’s FROM clause (but not in JOINs) with the specified mode (e.g. ‘EXCLUSIVE’).
-
#multi_insert_sql(columns, values) ⇒ Object
PostgreSQL allows inserting multiple rows at once.
-
#supports_cte_in_subqueries? ⇒ Boolean
PostgreSQL supports using the WITH clause in subqueries if it supports using WITH at all (i.e. on PostgreSQL 8.4+).
-
#supports_distinct_on? ⇒ Boolean
DISTINCT ON is a PostgreSQL extension.
-
#supports_modifying_joins? ⇒ Boolean
PostgreSQL supports modifying joined datasets.
-
#supports_returning?(type) ⇒ Boolean
Returning is always supported.
-
#supports_timestamp_timezones? ⇒ Boolean
PostgreSQL supports timezones in literal timestamps.
-
#supports_window_functions? ⇒ Boolean
PostgreSQL 8.4+ supports window functions.
-
#truncate(opts = {}) ⇒ Object
Truncates the dataset.
-
#window(name, opts) ⇒ Object
Return a clone of the dataset with an addition named window that can be referenced in window functions.
Instance Method Details
#analyze ⇒ Object
Return the results of an EXPLAIN ANALYZE query as a string
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# File 'lib/sequel/adapters/shared/postgres.rb', line 744 def analyze explain(:analyze=>true) end |
#complex_expression_sql_append(sql, op, args) ⇒ Object
Handle converting the ruby xor operator (^) into the PostgreSQL xor operator (#).
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# File 'lib/sequel/adapters/shared/postgres.rb', line 750 def complex_expression_sql_append(sql, op, args) case op when :^ j = XOR_OP c = false args.each do |a| sql << j if c literal_append(sql, a) c ||= true end else super end end |
#explain(opts = {}) ⇒ Object
Return the results of an EXPLAIN query as a string
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# File 'lib/sequel/adapters/shared/postgres.rb', line 766 def explain(opts={}) with_sql((opts[:analyze] ? EXPLAIN_ANALYZE : EXPLAIN) + select_sql).map(QUERY_PLAN).join(CRLF) end |
#for_share ⇒ Object
Return a cloned dataset which will use FOR SHARE to lock returned rows.
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# File 'lib/sequel/adapters/shared/postgres.rb', line 771 def for_share lock_style(:share) end |
#full_text_search(cols, terms, opts = {}) ⇒ Object
PostgreSQL specific full text search syntax, using tsearch2 (included in 8.3 by default, and available for earlier versions as an add-on).
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# File 'lib/sequel/adapters/shared/postgres.rb', line 777 def full_text_search(cols, terms, opts = {}) lang = opts[:language] || 'simple' terms = terms.join(' | ') if terms.is_a?(Array) filter("to_tsvector(?::regconfig, ?) @@ to_tsquery(?::regconfig, ?)", lang, full_text_string_join(cols), lang, terms) end |
#insert(*values) ⇒ Object
Insert given values into the database.
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# File 'lib/sequel/adapters/shared/postgres.rb', line 784 def insert(*values) if @opts[:returning] # already know which columns to return, let the standard code # handle it super elsif @opts[:sql] # raw SQL used, so don't know which table is being inserted # into, and therefore can't determine primary key. Run the # insert statement and return nil. super nil else # Force the use of RETURNING with the primary key value. returning(insert_pk).insert(*values){|r| return r.values.first} end end |
#insert_select(*values) ⇒ Object
Insert a record returning the record inserted
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# File 'lib/sequel/adapters/shared/postgres.rb', line 802 def insert_select(*values) returning.insert(*values){|r| return r} end |
#lock(mode, opts = {}) ⇒ Object
Locks all tables in the dataset’s FROM clause (but not in JOINs) with the specified mode (e.g. ‘EXCLUSIVE’). If a block is given, starts a new transaction, locks the table, and yields. If a block is not given just locks the tables. Note that PostgreSQL will probably raise an error if you lock the table outside of an existing transaction. Returns nil.
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# File 'lib/sequel/adapters/shared/postgres.rb', line 811 def lock(mode, opts={}) if block_given? # perform locking inside a transaction and yield to block @db.transaction(opts){lock(mode, opts); yield} else @db.execute(LOCK % [source_list(@opts[:from]), mode], opts) # lock without a transaction end nil end |
#multi_insert_sql(columns, values) ⇒ Object
PostgreSQL allows inserting multiple rows at once.
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# File 'lib/sequel/adapters/shared/postgres.rb', line 821 def multi_insert_sql(columns, values) sql = LiteralString.new('VALUES ') expression_list_append(sql, values.map{|r| Array(r)}) [insert_sql(columns, sql)] end |
#supports_cte_in_subqueries? ⇒ Boolean
PostgreSQL supports using the WITH clause in subqueries if it supports using WITH at all (i.e. on PostgreSQL 8.4+).
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# File 'lib/sequel/adapters/shared/postgres.rb', line 829 def supports_cte_in_subqueries? supports_cte? end |
#supports_distinct_on? ⇒ Boolean
DISTINCT ON is a PostgreSQL extension
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# File 'lib/sequel/adapters/shared/postgres.rb', line 834 def supports_distinct_on? true end |
#supports_modifying_joins? ⇒ Boolean
PostgreSQL supports modifying joined datasets
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# File 'lib/sequel/adapters/shared/postgres.rb', line 839 def true end |
#supports_returning?(type) ⇒ Boolean
Returning is always supported.
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# File 'lib/sequel/adapters/shared/postgres.rb', line 844 def supports_returning?(type) true end |
#supports_timestamp_timezones? ⇒ Boolean
PostgreSQL supports timezones in literal timestamps
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# File 'lib/sequel/adapters/shared/postgres.rb', line 849 def true end |
#supports_window_functions? ⇒ Boolean
PostgreSQL 8.4+ supports window functions
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# File 'lib/sequel/adapters/shared/postgres.rb', line 854 def supports_window_functions? server_version >= 80400 end |
#truncate(opts = {}) ⇒ Object
Truncates the dataset. Returns nil.
Options:
- :cascade
-
whether to use the CASCADE option, useful when truncating
tables with Foreign Keys.
- :only
-
truncate using ONLY, so child tables are unaffected
- :restart
-
use RESTART IDENTITY to restart any related sequences
:only and :restart only work correctly on PostgreSQL 8.4+.
Usage:
DB[:table].truncate # TRUNCATE TABLE "table"
# => nil
DB[:table].truncate(:cascade => true, :only=>true, :restart=>true) # TRUNCATE TABLE ONLY "table" RESTART IDENTITY CASCADE
# => nil
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# File 'lib/sequel/adapters/shared/postgres.rb', line 873 def truncate(opts = {}) if opts.empty? super() else clone(:truncate_opts=>opts).truncate end end |
#window(name, opts) ⇒ Object
Return a clone of the dataset with an addition named window that can be referenced in window functions.
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# File 'lib/sequel/adapters/shared/postgres.rb', line 882 def window(name, opts) clone(:window=>(@opts[:window]||[]) + [[name, SQL::Window.new(opts)]]) end |