764 commands · 48 cheat sheets · 6 subcategories
SQL master quick reference — Page 3
Browse 195 commands from 12 focused cheat sheets on page 3 of 4. Each example opens its matching detailed section.
Performance and Planning · 17 commands
PostgreSQL Parallel Query and JIT Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| Find parallel nodes | EXPLAIN (COSTS, VERBOSE)
SELECT count(*)
FROM app.orders; | View examples |
| Measure workers launched | EXPLAIN (ANALYZE, SUMMARY)
SELECT count(*)
FROM app.orders; | View examples |
| Show worker detail | EXPLAIN (ANALYZE, VERBOSE)
SELECT count(*)
FROM app.orders; | View examples |
| Set a local worker cap | SET LOCAL max_parallel_workers_per_gather = 4; | View examples |
| Inspect worker settings | SELECT name, setting
FROM pg_settings
WHERE name LIKE 'max_parallel%'; | View examples |
| Inspect setup cost | SHOW parallel_setup_cost; | View examples |
| Inspect table threshold | SHOW min_parallel_table_scan_size; | View examples |
| Label a function safe | ALTER FUNCTION app.net_amount(numeric, numeric) PARALLEL SAFE; | View examples |
| Label a function restricted | ALTER FUNCTION app.read_backend_state() PARALLEL RESTRICTED; | View examples |
| Disable parallel use | ALTER FUNCTION app.write_audit(text) PARALLEL UNSAFE; | View examples |
| Disable parallelism locally | SET LOCAL max_parallel_workers_per_gather = 0; | View examples |
| Check transaction isolation | SHOW transaction_isolation; | View examples |
| Enable JIT locally | SET LOCAL jit = on; | View examples |
| Inspect the JIT threshold | SHOW jit_above_cost; | View examples |
| Disable JIT locally | SET LOCAL jit = off; | View examples |
| Show JIT availability | SHOW jit_provider; | View examples |
| Track nondefault plan settings | EXPLAIN (SETTINGS, SUMMARY)
SELECT sum(total)
FROM app.orders; | View examples |
Performance and Planning · 16 commands
PostgreSQL Prepared Statements and Plan Caching Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| Prepare a typed query | PREPARE order_by_id (bigint) AS
SELECT id, status, total
FROM app.orders
WHERE id = $1; | View examples |
| Execute a statement | EXECUTE order_by_id(42001); | View examples |
| Prepare a write | PREPARE add_event (uuid, text) AS
INSERT INTO app.events(account_id, kind)
VALUES ($1, $2)
RETURNING id; | View examples |
| Fix parameter meaning | PREPARE events_since (timestamptz) AS
SELECT id
FROM app.events
WHERE occurred_at >= $1::timestamptz; | View examples |
| Inspect the chosen plan | EXPLAIN (ANALYZE, BUFFERS, SETTINGS) EXECUTE orders_for_tenant(42); | View examples |
| Test custom planning | SET LOCAL plan_cache_mode = 'force_custom_plan'; | View examples |
| Test generic planning | SET LOCAL plan_cache_mode = 'force_generic_plan'; | View examples |
| Restore automatic choice | SET plan_cache_mode = 'auto'; | View examples |
| List prepared statements | SELECT name,
parameter_types,
generic_plans,
custom_plans
FROM pg_prepared_statements
ORDER BY name; | View examples |
| Find generic-plan users | SELECT name, generic_plans, custom_plans
FROM pg_prepared_statements
WHERE generic_plans > 0; | View examples |
| Discard cached plans | DISCARD PLANS; | View examples |
| Release one statement | DEALLOCATE order_by_id; | View examples |
| Release all statements | DEALLOCATE ALL; | View examples |
| Pin object resolution | PREPARE active_accounts AS
SELECT id
FROM app.accounts
WHERE disabled_at IS NULL; | View examples |
| Check server version | SHOW server_version; | View examples |
| Identify two-phase state | SELECT gid, prepared, owner, database
FROM pg_prepared_xacts
ORDER BY prepared; | View examples |
Performance and Planning · 16 commands
PostgreSQL Statistics and Cardinality Estimation Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| Inspect estimated rows only | EXPLAIN SELECT * FROM app.orders WHERE status = 'open'; | View examples |
| Measure actual rows | EXPLAIN (ANALYZE, BUFFERS)
SELECT *
FROM app.orders
WHERE status = 'open'; | View examples |
| Expose planning settings | EXPLAIN (ANALYZE, SETTINGS)
SELECT count(*)
FROM app.orders; | View examples |
| Analyze one table | ANALYZE app.orders; | View examples |
| Analyze selected columns | ANALYZE app.orders (tenant_id, status); | View examples |
| Inspect table statistics | SELECT *
FROM pg_stats
WHERE schemaname = 'app' AND tablename = 'orders'; | View examples |
| Check approximate table size | SELECT reltuples, relpages
FROM pg_class
WHERE oid = 'app.orders'::regclass; | View examples |
| Set a column target | ALTER TABLE app.orders ALTER COLUMN tenant_id
SET STATISTICS 500; | View examples |
| Restore the default target | ALTER TABLE app.orders ALTER COLUMN tenant_id
SET STATISTICS DEFAULT; | View examples |
| Create dependency statistics | CREATE STATISTICS app.orders_dep (dependencies)
ON tenant_id, region
FROM app.orders; | View examples |
| Create MCV statistics | CREATE STATISTICS app.orders_mcv (mcv)
ON tenant_id, status
FROM app.orders; | View examples |
| Inspect extended statistics | SELECT *
FROM pg_stats_ext
WHERE statistics_name = 'orders_tenant_status'; | View examples |
| Set a proportional distinct estimate | ALTER TABLE app.events ALTER COLUMN tenant_id
SET (n_distinct = -0.02); | View examples |
| Remove a distinct override | ALTER TABLE app.events ALTER COLUMN tenant_id RESET (n_distinct); | View examples |
| Analyze a partition hierarchy | ANALYZE app.events; | View examples |
| Inspect extended-stat data safely | SELECT statistics_name, kinds
FROM pg_stats_ext
WHERE schemaname = 'app'; | View examples |
Performance and Planning · 17 commands
PostgreSQL System Catalogs and Information Schema Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| List visible tables | SELECT table_schema, table_name
FROM information_schema.tables
WHERE table_type = 'BASE TABLE'; | View examples |
| List PostgreSQL relations | SELECT oid::regclass, relkind
FROM pg_catalog.pg_class
WHERE relnamespace = 'app'::regnamespace; | View examples |
| Resolve the catalog schema | SELECT pg_catalog.current_schema(); | View examples |
| Resolve a relation OID | SELECT to_regclass('app.orders'); | View examples |
| Find a relation kind | SELECT relkind
FROM pg_class
WHERE oid = 'app.orders'::regclass; | View examples |
| List portable columns | SELECT column_name, data_type, is_nullable
FROM information_schema.columns
WHERE table_schema = 'app' AND table_name = 'orders'; | View examples |
| Render a PostgreSQL type | SELECT format_type(atttypid, atttypmod)
FROM pg_attribute
WHERE attrelid = 'app.orders'::regclass AND attnum > 0; | View examples |
| Resolve a type safely | SELECT to_regtype('pg_catalog.int8'); | View examples |
| Show index definitions | SELECT indexrelid::regclass,
indisvalid,
pg_get_indexdef(indexrelid)
FROM pg_index
WHERE indrelid = 'app.orders'::regclass; | View examples |
| Show a constraint definition | SELECT pg_get_constraintdef(oid)
FROM pg_constraint
WHERE conname = 'orders_pkey'; | View examples |
| Check table privilege | SELECT has_table_privilege('app_reader', 'app.orders', 'SELECT'); | View examples |
| Check schema usage | SELECT has_schema_privilege('app_reader', 'app', 'USAGE'); | View examples |
| Check function execution | SELECT has_function_privilege('app_reader', 'app.total(bigint)', 'EXECUTE'); | View examples |
| Describe a catalog object | SELECT pg_describe_object('pg_class'::regclass, 'app.orders'::regclass, 0); | View examples |
| Inspect dependencies | SELECT *
FROM pg_depend
WHERE refobjid = 'app.orders'::regclass; | View examples |
| Check server version number | SELECT current_setting('server_version_num')::int; | View examples |
| Check recovery state | SELECT pg_is_in_recovery(); | View examples |
Performance and Planning · 18 commands
PostgreSQL Table Partitioning and Pruning Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| Create a range-partitioned table | CREATE TABLE events (event_id bigint, occurred_at timestamptz NOT NULL) PARTITION BY RANGE (occurred_at); | View examples |
| Create a list-partitioned table | CREATE TABLE accounts (account_id bigint, region_code text NOT NULL) PARTITION BY LIST (region_code); | View examples |
| Create a hash-partitioned table | CREATE TABLE jobs (job_id bigint, tenant_id bigint NOT NULL) PARTITION BY HASH (tenant_id); | View examples |
| Create a monthly partition | CREATE TABLE events_2026_08 PARTITION OF events FOR
VALUES
FROM ('2026-08-01') TO ('2026-09-01'); | View examples |
| Create a default partition | CREATE TABLE events_default PARTITION OF events DEFAULT; | View examples |
| Create a list partition | CREATE TABLE accounts_americas PARTITION OF accounts FOR
VALUES IN ('BR', 'CA', 'US'); | View examples |
| Create a hash partition | CREATE TABLE jobs_h0 PARTITION OF jobs FOR
VALUES
WITH (MODULUS 4, REMAINDER 0); | View examples |
| Create matching child indexes | CREATE INDEX events_tenant_time_idx
ON events (tenant_id, occurred_at); | View examples |
| Declare partition-safe uniqueness | PRIMARY KEY (event_id, occurred_at) | View examples |
| Filter with matching range bounds | WHERE occurred_at >= TIMESTAMPTZ '2026-08-01 00:00:00+00' AND occurred_at < TIMESTAMPTZ '2026-09-01 00:00:00+00' | View examples |
| Inspect selected partitions | EXPLAIN (COSTS OFF)
SELECT count(*)
FROM events
WHERE occurred_at >= TIMESTAMPTZ '2026-08-01 00:00:00+00'; | View examples |
| Check pruning configuration | SHOW enable_partition_pruning; | View examples |
| Build an attachable table | CREATE TABLE events_2026_09 (LIKE events INCLUDING DEFAULTS INCLUDING CONSTRAINTS); | View examples |
| Validate the intended bound | ALTER TABLE events_2026_09 VALIDATE CONSTRAINT events_2026_09_bound; | View examples |
| Attach a prepared partition | ALTER TABLE events ATTACH PARTITION events_2026_09 FOR
VALUES
FROM ('2026-09-01') TO ('2026-10-01'); | View examples |
| List a partition hierarchy | SELECT relid, parentrelid, isleaf, level
FROM pg_partition_tree('events'::regclass); | View examples |
| Inspect partition bounds | SELECT relname, pg_get_expr(relpartbound, oid)
FROM pg_class
WHERE relispartition
ORDER BY relname; | View examples |
| Analyze the partitioned parent | ANALYZE events; | View examples |
Transactions and Security · 17 commands
PostgreSQL Advisory Locks Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| Lock for the transaction | SELECT pg_advisory_xact_lock(7001, 42); | View examples |
| Try a transaction lock | SELECT pg_try_advisory_xact_lock(7001, 42); | View examples |
| Take a shared lock | SELECT pg_advisory_xact_lock_shared(7001, 42); | View examples |
| Try a shared lock | SELECT pg_try_advisory_xact_lock_shared(7001, 42); | View examples |
| Lock for the session | SELECT pg_advisory_lock(8001, 17); | View examples |
| Try a session lock | SELECT pg_try_advisory_lock(8001, 17); | View examples |
| Unlock one session level | SELECT pg_advisory_unlock(8001, 17); | View examples |
| Unlock all session locks | SELECT pg_advisory_unlock_all(); | View examples |
| Bound lock waits | SET LOCAL lock_timeout = '2s'; | View examples |
| Order multiple keys | SELECT DISTINCT resource_id
FROM app.requested_resources
WHERE batch_id = 88
ORDER BY resource_id; | View examples |
| Limit before locking | SELECT pg_advisory_xact_lock(q.id)
FROM (
SELECT id
FROM app.jobs
ORDER BY id
LIMIT 10
) AS q; | View examples |
| List advisory locks | SELECT pid, mode, granted, classid, objid, objsubid
FROM pg_locks
WHERE locktype = 'advisory'; | View examples |
| Find advisory waiters | SELECT pid, mode, waitstart
FROM pg_locks
WHERE locktype = 'advisory' AND NOT granted
ORDER BY waitstart; | View examples |
| Find blocking processes | SELECT pid, pg_blocking_pids(pid) AS blockers
FROM pg_locks
WHERE locktype = 'advisory' AND NOT granted; | View examples |
| Use one 64-bit key | SELECT pg_try_advisory_xact_lock(9223372036854770000::bigint); | View examples |
| Namespace with two keys | SELECT pg_try_advisory_xact_lock(7001, 42); | View examples |
| Detect recovery | SELECT pg_is_in_recovery(); | View examples |
Transactions and Security · 17 commands
PostgreSQL Deadlocks, Timeouts, and Cancellation Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| Lock rows in key order | SELECT id
FROM app.accounts
WHERE id = ANY (ARRAY[41,72])
ORDER BY id FOR
UPDATE; | View examples |
| Lock a table explicitly | LOCK TABLE app.ledger IN SHARE ROW EXCLUSIVE MODE; | View examples |
| Inspect deadlock delay | SHOW deadlock_timeout; | View examples |
| Set transaction-local lock timeout | SET LOCAL lock_timeout = '2s'; | View examples |
| Disable the lock timeout | SET LOCAL lock_timeout = '0'; | View examples |
| Set a statement timeout | SET LOCAL statement_timeout = '30s'; | View examples |
| Set a role default | ALTER ROLE report_user SET statement_timeout = '30s'; | View examples |
| Inspect the timeout | SHOW statement_timeout; | View examples |
| Bound idle transactions | SET idle_in_transaction_session_timeout = '60s'; | View examples |
| Bound a transaction | SET transaction_timeout = '5min'; | View examples |
| Find blocking PIDs | SELECT pg_blocking_pids(12345); | View examples |
| List lock waiters | SELECT pid, wait_event, query
FROM pg_stat_activity
WHERE wait_event_type = 'Lock'; | View examples |
| Inspect held locks | SELECT * FROM pg_locks WHERE pid = 12345; | View examples |
| Cancel a backend query | SELECT pg_cancel_backend(12345); | View examples |
| Terminate a backend | SELECT pg_terminate_backend(12345, 5000); | View examples |
| Inspect lock-wait logging | SHOW log_lock_waits; | View examples |
| Inspect active transaction age | SELECT pid, xact_start, state
FROM pg_stat_activity
WHERE xact_start IS NOT NULL
ORDER BY xact_start; | View examples |
Transactions and Security · 16 commands
PostgreSQL Extensions and Extension Security Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| List available extensions | SELECT name, default_version, installed_version
FROM pg_available_extensions
ORDER BY name; | View examples |
| Inspect installable versions | SELECT version,
installed,
superuser,
trusted,
relocatable
FROM pg_available_extension_versions
WHERE name = 'pgcrypto'; | View examples |
| Create a controlled schema | CREATE SCHEMA extensions AUTHORIZATION extension_owner; | View examples |
| Protect the target schema | REVOKE CREATE ON SCHEMA extensions FROM PUBLIC; | View examples |
| Install a pinned version | CREATE EXTENSION pgcrypto
WITH SCHEMA extensions VERSION '1.3'; | View examples |
| Install only when absent | CREATE EXTENSION IF NOT EXISTS pgcrypto
WITH SCHEMA extensions VERSION '1.3'; | View examples |
| Inspect installed extensions | SELECT extname,
extversion,
extnamespace::regnamespace,
extrelocatable
FROM pg_extension
ORDER BY extname; | View examples |
| Inspect update paths | SELECT source, target, path
FROM pg_extension_update_paths('pgcrypto')
ORDER BY source, target; | View examples |
| Update to a reviewed version | ALTER EXTENSION pgcrypto UPDATE TO '1.3'; | View examples |
| Move a relocatable extension | ALTER EXTENSION pgcrypto SET SCHEMA extensions_v2; | View examples |
| List extension members | SELECT pg_describe_object(d.classid,d.objid,d.objsubid)
FROM pg_depend d
WHERE d.refobjid = (
SELECT oid
FROM pg_extension
WHERE extname='pgcrypto'
); | View examples |
| Attach an existing object | ALTER EXTENSION app_tools ADD FUNCTION app_tools.normalize_email(text); | View examples |
| Drop without cascading | DROP EXTENSION pgcrypto RESTRICT; | View examples |
| Preserve configuration data | SELECT pg_catalog.pg_extension_config_dump('app_tools.settings', 'WHERE NOT built_in'); | View examples |
| Secure an update script path | SELECT pg_catalog.set_config('search_path', 'pg_catalog, pg_temp', true); | View examples |
| Pin a function search path | ALTER FUNCTION extensions.secure_length(text)
SET search_path = pg_catalog, pg_temp; | View examples |
Transactions and Security · 18 commands
PostgreSQL pgcrypto and Data Encryption Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| Install pgcrypto | CREATE EXTENSION IF NOT EXISTS pgcrypto
WITH SCHEMA extensions; | View examples |
| Check its version | SELECT extversion
FROM pg_extension
WHERE extname = 'pgcrypto'; | View examples |
| Check FIPS mode | SELECT extensions.fips_mode(); | View examples |
| Hash text with SHA-256 | SELECT encode(extensions.digest('payload', 'sha256'), 'hex'); | View examples |
| Hash binary data | SELECT extensions.digest(decode('00ff', 'hex'), 'sha512'); | View examples |
| Create an HMAC | SELECT extensions.hmac('payload', 'secret-key', 'sha256'); | View examples |
| Encode an HMAC | SELECT encode(extensions.hmac('payload', 'secret-key', 'sha256'), 'base64'); | View examples |
| Generate a bcrypt hash | SELECT extensions.crypt('password', extensions.gen_salt('bf', 12)); | View examples |
| Verify a password | SELECT extensions.crypt('candidate', password_hash) = password_hash
FROM app.users
WHERE id = 42; | View examples |
| Generate SHA-512 crypt | SELECT extensions.crypt('password', extensions.gen_salt('sha512crypt', 100000)); | View examples |
| Encrypt text symmetrically | SELECT extensions.pgp_sym_encrypt('secret', 'passphrase', 'cipher-algo=aes256'); | View examples |
| Decrypt symmetric text | SELECT extensions.pgp_sym_decrypt(ciphertext, 'passphrase')
FROM app.secrets
WHERE secret_id = 42; | View examples |
| Encrypt binary data | SELECT extensions.pgp_sym_encrypt_bytea(decode('00ff', 'hex'), 'passphrase'); | View examples |
| Encrypt with a public key | SELECT extensions.pgp_pub_encrypt('secret', extensions.dearmor(public_key))
FROM app.keyring
WHERE key_id = 3; | View examples |
| Decrypt with a private key | SELECT extensions.pgp_pub_decrypt(ciphertext, extensions.dearmor(private_key), 'key-passphrase'); | View examples |
| Generate random bytes | SELECT extensions.gen_random_bytes(32); | View examples |
| Generate a random UUID | SELECT pg_catalog.gen_random_uuid(); | View examples |
| Check builtin crypto policy | SHOW pgcrypto.builtin_crypto_enabled; | View examples |
Transactions and Security · 14 commands
PostgreSQL Row-Level Security Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| Enable row security | ALTER TABLE app.invoice ENABLE ROW LEVEL SECURITY; | View examples |
| Apply RLS to the owner | ALTER TABLE app.invoice FORCE ROW LEVEL SECURITY; | View examples |
| Grant baseline privileges | GRANT
SELECT, INSERT,
UPDATE, DELETE
ON app.invoice TO app_runtime; | View examples |
| Filter visible rows | CREATE POLICY invoice_select
ON app.invoice FOR
SELECT TO app_runtime
USING (tenant_id = app.current_tenant_id()); | View examples |
| Validate inserted rows | CREATE POLICY invoice_insert
ON app.invoice FOR INSERT TO app_runtime
WITH CHECK (tenant_id = app.current_tenant_id()); | View examples |
| Constrain updates | CREATE POLICY inv_update
ON app.invoice FOR
UPDATE TO app_runtime
USING (tenant_id = app.current_tenant_id())
WITH CHECK (tenant_id = app.current_tenant_id()); | View examples |
| Add an allow path | CREATE POLICY support_read
ON app.invoice AS PERMISSIVE FOR
SELECT TO support_agent
USING (assigned_to = current_user); | View examples |
| Add a mandatory condition | CREATE POLICY no_legal_hold_delete
ON app.invoice AS RESTRICTIVE FOR DELETE TO app_runtime
USING (NOT legal_hold); | View examples |
| Remove RLS bypass | ALTER ROLE app_runtime NOBYPASSRLS; | View examples |
| Error instead of filtering | SET LOCAL row_security = off; | View examples |
| Scope tenant context | SET LOCAL app.tenant_id = '42'; | View examples |
| Read optional context | SELECT current_setting('app.tenant_id', true); | View examples |
| Inspect effective definitions | SELECT *
FROM pg_policies
WHERE schemaname = 'app' AND tablename = 'invoice'; | View examples |
| Check RLS for this caller | SELECT row_security_active('app.invoice'::regclass); | View examples |
Transactions and Security · 12 commands
PostgreSQL Schemas, Roles, and Privileges Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| Create a schema | CREATE SCHEMA app AUTHORIZATION app_owner; | View examples |
| Set role search path | ALTER ROLE app_runtime
SET search_path = app, pg_catalog; | View examples |
| Create a login role | CREATE ROLE app_runtime LOGIN PASSWORD NULL; | View examples |
| Create a group role | CREATE ROLE app_readonly NOLOGIN; | View examples |
| Grant role membership | GRANT app_readonly TO analyst_user; | View examples |
| Allow schema lookup | GRANT USAGE ON SCHEMA app TO app_readonly; | View examples |
| Grant existing table reads | GRANT
SELECT
ON ALL TABLES IN SCHEMA app TO app_readonly; | View examples |
| Grant sequence use | GRANT USAGE,
SELECT
ON ALL SEQUENCES IN SCHEMA app TO app_runtime; | View examples |
| Revoke public schema creation | REVOKE CREATE ON SCHEMA public FROM PUBLIC; | View examples |
| Grant future table reads | ALTER DEFAULT PRIVILEGES FOR ROLE app_owner IN SCHEMA app GRANT
SELECT
ON TABLES TO app_readonly; | View examples |
| Test a privilege | SELECT has_table_privilege('app_runtime', 'app.orders', 'SELECT'); | View examples |
| Transfer ownership | ALTER TABLE app.orders OWNER TO app_owner; | View examples |
Transactions and Security · 17 commands
PostgreSQL Transactions and Locking Cheat Sheet
| Use | Syntax | Examples |
|---|---|---|
| Start a transaction | BEGIN; | View examples |
| Commit changes | COMMIT; | View examples |
| Discard changes | ROLLBACK; | View examples |
| Create a savepoint | SAVEPOINT before_optional_step; | View examples |
| Roll back partway | ROLLBACK TO SAVEPOINT before_optional_step; | View examples |
| Release a savepoint | RELEASE SAVEPOINT before_optional_step; | View examples |
| Use read committed | BEGIN ISOLATION LEVEL READ COMMITTED; | View examples |
| Use repeatable read | BEGIN ISOLATION LEVEL REPEATABLE READ; | View examples |
| Use serializable | BEGIN ISOLATION LEVEL SERIALIZABLE; | View examples |
| Declare read-only work | BEGIN READ ONLY; | View examples |
| Limit statement duration locally | SET LOCAL statement_timeout = '5s'; | View examples |
| Lock selected rows | SELECT * FROM accounts WHERE id = 42 FOR UPDATE; | View examples |
| Use a weaker update lock | SELECT * FROM accounts WHERE id = 42 FOR NO KEY UPDATE; | View examples |
| Fail instead of waiting | SELECT * FROM jobs WHERE id = 7 FOR UPDATE NOWAIT; | View examples |
| Skip locked work | SELECT *
FROM jobs
WHERE status = 'ready'
ORDER BY id FOR
UPDATE SKIP LOCKED
LIMIT 1; | View examples |
| Lock a table explicitly | LOCK TABLE reports IN SHARE MODE; | View examples |
| Lock in stable order | SELECT *
FROM accounts
WHERE id IN (1, 2)
ORDER BY id FOR
UPDATE; | View examples |