Module: Sequel::Postgres::DatasetMethods

Includes:
UnmodifiedIdentifiers::DatasetMethods
Included in:
JDBC::Postgres::Dataset, Dataset
Defined in:
lib/sequel/adapters/shared/postgres.rb

Constant Summary collapse

NULL = 
LiteralString.new('NULL').freeze
LOCK_MODES = 
['ACCESS SHARE', 'ROW SHARE', 'ROW EXCLUSIVE', 'SHARE UPDATE EXCLUSIVE', 'SHARE', 'SHARE ROW EXCLUSIVE', 'EXCLUSIVE', 'ACCESS EXCLUSIVE'].each(&:freeze).freeze

Instance Method Summary collapse

Instance Method Details

#analyze ⇒ Object

Return the results of an EXPLAIN ANALYZE query as a string



2970
2971
2972
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 2970

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 (#), and use the ILIKE and NOT ILIKE operators.



2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 2977

def complex_expression_sql_append(sql, op, args)
  case op
  when :^
    j = ' # '
    c = false
    args.each do |a|
      sql << j if c
      literal_append(sql, a)
      c ||= true
    end
  when :ILIKE, :'NOT ILIKE'
    sql << '('
    literal_append(sql, args[0])
    sql << ' ' << op.to_s << ' '
    literal_append(sql, args[1])
    sql << ')'
  else
    super
  end
end

#disable_insert_returning ⇒ Object

Disables automatic use of INSERT ... RETURNING. You can still use returning manually to force the use of RETURNING when inserting.

This is designed for cases where INSERT RETURNING cannot be used, such as when you are using partitioning with trigger functions or conditional rules, or when you are using a PostgreSQL version less than 8.2, or a PostgreSQL derivative that does not support returning.

Note that when this method is used, insert will not return the primary key of the inserted row, you will have to get the primary key of the inserted row before inserting via nextval, or after inserting via currval or lastval (making sure to use the same database connection for currval or lastval).



3012
3013
3014
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3012

def disable_insert_returning
  clone(:disable_insert_returning=>true)
end

#empty? ⇒ Boolean

Always return false when using VALUES

Returns:

  • (Boolean) 


3017
3018
3019
3020
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3017

def empty?
  return false if @opts[:values]
  super
end

#explain(opts = OPTS) ⇒ Object

Return the results of an EXPLAIN query. Boolean options:

:analyze :: Use the ANALYZE option. :buffers :: Use the BUFFERS option. :costs :: Use the COSTS option. :generic_plan :: Use the GENERIC_PLAN option. :memory :: Use the MEMORY option. :settings :: Use the SETTINGS option. :summary :: Use the SUMMARY option. :timing :: Use the TIMING option. :verbose :: Use the VERBOSE option. :wal :: Use the WAL option.

Non boolean options:

:format :: Use the FORMAT option to change the format of the returned value. Values can be :text, :xml, :json, or :yaml. :serialize :: Use the SERIALIZE option to get timing on serialization. Values can be :none, :text, or :binary.

See the PostgreSQL EXPLAIN documentation for an explanation of what each option does.

In most cases, the return value is a single string. However, using the format: :json option can result in the return value being an array containing a hash.



3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3050

def explain(opts=OPTS)
  rows = clone(:append_sql=>explain_sql_string_origin(opts)).map(:'QUERY PLAN')

  if rows.length == 1
    rows[0]
  elsif rows.all?{|row| String === row}
    rows.join("\r\n") 
  # :nocov:
  else
    # This branch is unreachable in tests, but it seems better to just return
    # all rows than throw in error if this case actually happens.
    rows
  # :nocov:
  end
end

#for_key_share ⇒ Object

Return a cloned dataset which will use FOR KEY SHARE to lock returned rows. Supported on PostgreSQL 9.3+.



3068
3069
3070
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3068

def for_key_share
  cached_lock_style_dataset(:_for_key_share_ds, :key_share)
end

#for_no_key_update ⇒ Object

Return a cloned dataset which will use FOR NO KEY UPDATE to lock returned rows. This is generally a better choice than using for_update on PostgreSQL, unless you will be deleting the row or modifying a key column. Supported on PostgreSQL 9.3+.



3095
3096
3097
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3095

def for_no_key_update
  cached_lock_style_dataset(:_for_no_key_update_ds, :no_key_update)
end

#for_portion_of(column, range, to = (arg_not_given=true)) ⇒ Object

Set FOR PORTION OF clause for UPDATE and DELETE statements. The first argument is the range or multirange column. If two arguments are provided, the second argument is an expression with the same database type as the first argument. If three arguments are provided, the second specifies the inclusive start of the portion to update and the third specifies the exclusive end of portion to update. When using the three argument form, nil can be provided as the second or third argument to have the start or end of the portion be unbounded. Supported on PostgreSQL 19+. Example:

DB[:t].for_portion_of(:rc, Sequel.function(:int4range, 1, 2)).update(c: 3)
# UPDATE t FOR PORTION OF rc (int4range(1, 2)) SET c = 3

DB[:t].for_portion_of(:rc, 1, 2).update(c: 3)
# UPDATE t FOR PORTION OF rc FROM 1 TO 2 SET c = 3


3087
3088
3089
3090
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3087

def for_portion_of(column, range, to=(arg_not_given=true))
  range = [range, to].freeze unless arg_not_given
  clone(:for_portion_of => [column, range].freeze)
end

#for_share ⇒ Object

Return a cloned dataset which will use FOR SHARE to lock returned rows.



3100
3101
3102
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3100

def for_share
  cached_lock_style_dataset(:_for_share_ds, :share)
end

#full_text_search(cols, terms, opts = OPTS) ⇒ Object

Run a full text search on PostgreSQL. By default, searching for the inclusion of any of the terms in any of the cols.

Options: :headline :: Append a expression to the selected columns aliased to headline that contains an extract of the matched text. :language :: The language to use for the search (default: 'simple') :plain :: Whether a plain search should be used (default: false). In this case, terms should be a single string, and it will do a search where cols contains all of the words in terms. This ignores search operators in terms. :phrase :: Similar to :plain, but also adding an ILIKE filter to ensure that returned rows also include the exact phrase used. :rank :: Set to true to order by the rank, so that closer matches are returned first. :to_tsquery :: Can be set to :plain, :phrase, or :websearch to specify the function to use to convert the terms to a ts_query. :tsquery :: Specifies the terms argument is already a valid SQL expression returning a tsquery, and can be used directly in the query. :tsvector :: Specifies the cols argument is already a valid SQL expression returning a tsvector, and can be used directly in the query.



3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3123

def full_text_search(cols, terms, opts = OPTS)
  lang = Sequel.cast(opts[:language] || 'simple', :regconfig)

  unless opts[:tsvector]
    phrase_cols = full_text_string_join(cols)
    cols = Sequel.function(:to_tsvector, lang, phrase_cols)
  end

  unless opts[:tsquery]
    phrase_terms = terms.is_a?(Array) || terms.is_a?(Set) ? Sequel.array_or_set_join(terms, ' | ') : terms

    query_func = case to_tsquery = opts[:to_tsquery]
    when :phrase, :plain
      :"#{to_tsquery}to_tsquery"
    when :websearch
      :"websearch_to_tsquery"
    else
      (opts[:phrase] || opts[:plain]) ? :plainto_tsquery : :to_tsquery
    end

    terms = Sequel.function(query_func, lang, phrase_terms)
  end

  ds = where(Sequel.lit(["", " @@ ", ""], cols, terms))

  if opts[:phrase]
    raise Error, "can't use :phrase with either :tsvector or :tsquery arguments to full_text_search together" if opts[:tsvector] || opts[:tsquery]
    ds = ds.grep(phrase_cols, "%#{escape_like(phrase_terms)}%", :case_insensitive=>true)
  end

  if opts[:rank]
    ds = ds.reverse{ts_rank_cd(cols, terms)}
  end

  if opts[:headline]
    ds = ds.select_append{ts_headline(lang, phrase_cols, terms).as(:headline)}
  end

  ds
end

#insert(*values) ⇒ Object

Insert given values into the database.



3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3165

def insert(*values)
  if @opts[:returning]
    # Already know which columns to return, let the standard code handle it
    super
  elsif @opts[:sql] || @opts[:disable_insert_returning]
    # Raw SQL used or RETURNING disabled, just use the default behavior
    # and return nil since sequence is not known.
    super
    nil
  else
    # Force the use of RETURNING with the primary key value,
    # unless it has been disabled.
    returning(insert_pk).insert(*values){|r| return r.values.first}
  end
end

#insert_conflict(opts = OPTS) ⇒ Object

Handle uniqueness violations when inserting, by updating the conflicting row, using ON CONFLICT. With no options, uses ON CONFLICT DO NOTHING. Options: :conflict_where :: The index filter, when using a partial index to determine uniqueness. :constraint :: An explicit constraint name, has precendence over :target. :target :: The column name or expression to handle uniqueness violations on. :update :: A hash of columns and values to set. Uses ON CONFLICT DO UPDATE. :update_where :: A WHERE condition to use for the update.

Examples:

DB[:table].insert_conflict.insert(a: 1, b: 2)
# INSERT INTO TABLE (a, b) VALUES (1, 2)
# ON CONFLICT DO NOTHING

DB[:table].insert_conflict(constraint: :table_a_uidx).insert(a: 1, b: 2)
# INSERT INTO TABLE (a, b) VALUES (1, 2)
# ON CONFLICT ON CONSTRAINT table_a_uidx DO NOTHING

DB[:table].insert_conflict(target: :a).insert(a: 1, b: 2)
# INSERT INTO TABLE (a, b) VALUES (1, 2)
# ON CONFLICT (a) DO NOTHING

DB[:table].insert_conflict(target: :a, conflict_where: {c: true}).insert(a: 1, b: 2)
# INSERT INTO TABLE (a, b) VALUES (1, 2)
# ON CONFLICT (a) WHERE (c IS TRUE) DO NOTHING

DB[:table].insert_conflict(target: :a, update: {b: Sequel[:excluded][:b]}).insert(a: 1, b: 2)
# INSERT INTO TABLE (a, b) VALUES (1, 2)
# ON CONFLICT (a) DO UPDATE SET b = excluded.b

DB[:table].insert_conflict(constraint: :table_a_uidx,
update: {b: Sequel[:excluded][:b]}, update_where: {Sequel[:table][:status_id] => 1}).insert(a: 1, b: 2)
# INSERT INTO TABLE (a, b) VALUES (1, 2)
# ON CONFLICT ON CONSTRAINT table_a_uidx
# DO UPDATE SET b = excluded.b WHERE (table.status_id = 1)


3216
3217
3218
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3216

def insert_conflict(opts=OPTS)
  clone(:insert_conflict => opts)
end

#insert_ignore ⇒ Object

Ignore uniqueness/exclusion violations when inserting, using ON CONFLICT DO NOTHING. Exists mostly for compatibility to MySQL's insert_ignore. Example:

DB[:table].insert_ignore.insert(a: 1, b: 2)
# INSERT INTO TABLE (a, b) VALUES (1, 2)
# ON CONFLICT DO NOTHING


3226
3227
3228
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3226

def insert_ignore
  insert_conflict
end

#insert_select(*values) ⇒ Object

Insert a record, returning the record inserted, using RETURNING. Always returns nil without running an INSERT statement if disable_insert_returning is used. If the query runs but returns no values, returns false.



3233
3234
3235
3236
3237
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3233

def insert_select(*values)
  return unless supports_insert_select?
  # Handle case where query does not return a row
  server?(:default).with_sql_first(insert_select_sql(*values)) || false
end

#insert_select_sql(*values) ⇒ Object

The SQL to use for an insert_select, adds a RETURNING clause to the insert unless the RETURNING clause is already present.



3241
3242
3243
3244
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3241

def insert_select_sql(*values)
  ds = opts[:returning] ? self : returning
  ds.insert_sql(*values)
end

#join_table(type, table, expr = nil, options = OPTS, &block) ⇒ Object

Support SQL::AliasedExpression as expr to setup a USING join with a table alias for the USING columns.



3248
3249
3250
3251
3252
3253
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3248

def join_table(type, table, expr=nil, options=OPTS, &block)
  if expr.is_a?(SQL::AliasedExpression) && expr.expression.is_a?(Array) && !expr.expression.empty? && expr.expression.all?
    options = options.merge(:join_using=>true)
  end
  super
end

#lock(mode, opts = 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.



3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3260

def lock(mode, opts=OPTS)
  if defined?(yield) # perform locking inside a transaction and yield to block
    @db.transaction(opts){lock(mode, opts); yield}
  else
    sql = 'LOCK TABLE '.dup
    source_list_append(sql, @opts[:from])
    mode = mode.to_s.upcase.strip
    unless LOCK_MODES.include?(mode)
      raise Error, "Unsupported lock mode: #{mode}"
    end
    sql << " IN #{mode} MODE"
    @db.execute(sql, opts)
  end
  nil
end

#merge(&block) ⇒ Object

Support MERGE RETURNING on PostgreSQL 17+.



3277
3278
3279
3280
3281
3282
3283
3284
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3277

def merge(&block)
  sql = merge_sql
  if uses_returning?(:merge)
    returning_fetch_rows(sql, &block)
  else
    execute_ddl(sql)
  end
end

#merge_delete_when_not_matched_by_source(&block) ⇒ Object

Return a dataset with a WHEN NOT MATCHED BY SOURCE THEN DELETE clause added to the MERGE statement. If a block is passed, treat it as a virtual row and use it as additional conditions for the match.

merge_delete_not_matched_by_source
# WHEN NOT MATCHED BY SOURCE THEN DELETE

merge_delete_not_matched_by_source{a > 30}
# WHEN NOT MATCHED BY SOURCE AND (a > 30) THEN DELETE


3295
3296
3297
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3295

def merge_delete_when_not_matched_by_source(&block)
  _merge_when(:type=>:delete_not_matched_by_source, &block)
end

#merge_do_nothing_when_matched(&block) ⇒ Object

Return a dataset with a WHEN MATCHED THEN DO NOTHING clause added to the MERGE statement. If a block is passed, treat it as a virtual row and use it as additional conditions for the match.

merge_do_nothing_when_matched
# WHEN MATCHED THEN DO NOTHING

merge_do_nothing_when_matched{a > 30}
# WHEN MATCHED AND (a > 30) THEN DO NOTHING


3308
3309
3310
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3308

def merge_do_nothing_when_matched(&block)
  _merge_when(:type=>:matched, &block)
end

#merge_do_nothing_when_not_matched(&block) ⇒ Object

Return a dataset with a WHEN NOT MATCHED THEN DO NOTHING clause added to the MERGE statement. If a block is passed, treat it as a virtual row and use it as additional conditions for the match.

merge_do_nothing_when_not_matched
# WHEN NOT MATCHED THEN DO NOTHING

merge_do_nothing_when_not_matched{a > 30}
# WHEN NOT MATCHED AND (a > 30) THEN DO NOTHING


3321
3322
3323
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3321

def merge_do_nothing_when_not_matched(&block)
  _merge_when(:type=>:not_matched, &block)
end

#merge_do_nothing_when_not_matched_by_source(&block) ⇒ Object

Return a dataset with a WHEN NOT MATCHED BY SOURCE THEN DO NOTHING clause added to the MERGE BY SOURCE statement. If a block is passed, treat it as a virtual row and use it as additional conditions for the match.

merge_do_nothing_when_not_matched_by_source
# WHEN NOT MATCHED BY SOURCE THEN DO NOTHING

merge_do_nothing_when_not_matched_by_source{a > 30}
# WHEN NOT MATCHED BY SOURCE AND (a > 30) THEN DO NOTHING


3334
3335
3336
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3334

def merge_do_nothing_when_not_matched_by_source(&block)
  _merge_when(:type=>:not_matched_by_source, &block)
end

#merge_insert(*values, &block) ⇒ Object

Support OVERRIDING USER|SYSTEM VALUE for MERGE INSERT.



3339
3340
3341
3342
3343
3344
3345
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3339

def merge_insert(*values, &block)
  h = {:type=>:insert, :values=>values}
  if @opts[:override]
    h[:override] = insert_override_sql(String.new)
  end
  _merge_when(h, &block)
end

#merge_update_when_not_matched_by_source(values, &block) ⇒ Object

Return a dataset with a WHEN NOT MATCHED BY SOURCE THEN UPDATE clause added to the MERGE statement. If a block is passed, treat it as a virtual row and use it as additional conditions for the match.

merge_update_not_matched_by_source(i1: Sequel[:i1]+:i2+10, a: Sequel[:a]+:b+20)
# WHEN NOT MATCHED BY SOURCE THEN UPDATE SET i1 = (i1 + i2 + 10), a = (a + b + 20)

merge_update_not_matched_by_source(i1: :i2){a > 30}
# WHEN NOT MATCHED BY SOURCE AND (a > 30) THEN UPDATE SET i1 = i2


3356
3357
3358
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3356

def merge_update_when_not_matched_by_source(values, &block)
  _merge_when(:type=>:update_not_matched_by_source, :values=>values, &block)
end

#overriding_system_value ⇒ Object

Use OVERRIDING USER VALUE for INSERT statements, so that identity columns always use the user supplied value, and an error is not raised for identity columns that are GENERATED ALWAYS.



3363
3364
3365
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3363

def overriding_system_value
  clone(:override=>:system)
end

#overriding_user_value ⇒ Object

Use OVERRIDING USER VALUE for INSERT statements, so that identity columns always use the sequence value instead of the user supplied value.



3369
3370
3371
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3369

def overriding_user_value
  clone(:override=>:user)
end

#supports_cte?(type = :select) ⇒ Boolean

Returns:

  • (Boolean) 


3373
3374
3375
3376
3377
3378
3379
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3373

def supports_cte?(type=:select)
  if type == :select
    server_version >= 80400
  else
    server_version >= 90100
  end
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+).

Returns:

  • (Boolean) 


3383
3384
3385
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3383

def supports_cte_in_subqueries?
  supports_cte?
end

#supports_distinct_on? ⇒ Boolean

DISTINCT ON is a PostgreSQL extension

Returns:

  • (Boolean) 


3388
3389
3390
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3388

def supports_distinct_on?
  true
end

#supports_group_cube? ⇒ Boolean

PostgreSQL 9.5+ supports GROUP CUBE

Returns:

  • (Boolean) 


3393
3394
3395
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3393

def supports_group_cube?
  server_version >= 90500
end

#supports_group_rollup? ⇒ Boolean

PostgreSQL 9.5+ supports GROUP ROLLUP

Returns:

  • (Boolean) 


3398
3399
3400
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3398

def supports_group_rollup?
  server_version >= 90500
end

#supports_grouping_sets? ⇒ Boolean

PostgreSQL 9.5+ supports GROUPING SETS

Returns:

  • (Boolean) 


3403
3404
3405
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3403

def supports_grouping_sets?
  server_version >= 90500
end

#supports_insert_conflict? ⇒ Boolean

PostgreSQL 9.5+ supports the ON CONFLICT clause to INSERT.

Returns:

  • (Boolean) 


3413
3414
3415
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3413

def supports_insert_conflict?
  server_version >= 90500
end

#supports_insert_select? ⇒ Boolean

True unless insert returning has been disabled for this dataset.

Returns:

  • (Boolean) 


3408
3409
3410
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3408

def supports_insert_select?
  !@opts[:disable_insert_returning]
end

#supports_lateral_subqueries? ⇒ Boolean

PostgreSQL 9.3+ supports lateral subqueries

Returns:

  • (Boolean) 


3418
3419
3420
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3418

def supports_lateral_subqueries?
  server_version >= 90300
end

#supports_merge? ⇒ Boolean

PostgreSQL 15+ supports MERGE.

Returns:

  • (Boolean) 


3428
3429
3430
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3428

def supports_merge?
  server_version >= 150000
end

#supports_modifying_joins? ⇒ Boolean

PostgreSQL supports modifying joined datasets

Returns:

  • (Boolean) 


3423
3424
3425
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3423

def supports_modifying_joins?
  true
end

#supports_nowait? ⇒ Boolean

PostgreSQL supports NOWAIT.

Returns:

  • (Boolean) 


3433
3434
3435
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3433

def supports_nowait?
  true
end

#supports_regexp? ⇒ Boolean

PostgreSQL supports pattern matching via regular expressions

Returns:

  • (Boolean) 


3448
3449
3450
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3448

def supports_regexp?
  true
end

#supports_returning?(type) ⇒ Boolean

MERGE RETURNING is supported on PostgreSQL 17+. Other RETURNING is supported on all supported PostgreSQL versions.

Returns:

  • (Boolean) 


3439
3440
3441
3442
3443
3444
3445
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3439

def supports_returning?(type)
  if type == :merge
    server_version >= 170000
  else
    true
  end
end

#supports_skip_locked? ⇒ Boolean

PostgreSQL 9.5+ supports SKIP LOCKED.

Returns:

  • (Boolean) 


3453
3454
3455
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3453

def supports_skip_locked?
  server_version >= 90500
end

#supports_timestamp_timezones? ⇒ Boolean

PostgreSQL supports timezones in literal timestamps

Returns:

  • (Boolean) 


3460
3461
3462
3463
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3460

def supports_timestamp_timezones?
  # SEQUEL6: Remove
  true
end

#supports_window_clause? ⇒ Boolean

PostgreSQL 8.4+ supports WINDOW clause.

Returns:

  • (Boolean) 


3467
3468
3469
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3467

def supports_window_clause?
  server_version >= 80400
end

#supports_window_function_frame_option?(option) ⇒ Boolean

Base support added in 8.4, offset supported added in 9.0, GROUPS and EXCLUDE support added in 11.0.

Returns:

  • (Boolean) 


3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3478

def supports_window_function_frame_option?(option)
  case option
  when :rows, :range
    true
  when :offset
    server_version >= 90000
  when :groups, :exclude
    server_version >= 110000
  else
    false
  end
end

#supports_window_functions? ⇒ Boolean

PostgreSQL 8.4+ supports window functions

Returns:

  • (Boolean) 


3472
3473
3474
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3472

def supports_window_functions?
  server_version >= 80400
end

#truncate(opts = 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"

DB[:table].truncate(cascade: true, only: true, restart: true)
# TRUNCATE TABLE ONLY "table" RESTART IDENTITY CASCADE


3507
3508
3509
3510
3511
3512
3513
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3507

def truncate(opts = OPTS)
  if opts.empty?
    super()
  else
    clone(:truncate_opts=>opts).truncate
  end
end

#with_ties ⇒ Object

Use WITH TIES when limiting the result set to also include additional rules that have the same results for the order column as the final row. Requires PostgreSQL 13.



3518
3519
3520
 
# File 'lib/sequel/adapters/shared/postgres.rb', line 3518

def with_ties
  clone(:limit_with_ties=>true)
end