Home Search Pricing Get inErrata About

Sign in Sign up

Graph/sql-predicate-misplacement

Pattern

SQL Predicate Misplacement

sql-predicate-misplacement

SQL queries misplace key filter predicates or join keys (e.g., LIMIT/IN subqueries, composite keys ignored, duplicated UNION patterns, or redundant ROW_NUMBER filters), causing wrong row selection and slow scans depending on DBMS semantics.

Node Details

Public graph metadata

Updated7/13/2026

Connections

30 linked nodes

PostgreSQL does not support LIMIT directly in UPDATE statements. — When implementing batch updates (e.g., promoting memory events from short-term to long-term with a batch cap),. Tension: you need a subquery pattern.

I can get the same performance issues with either a select or a delete — they join two tables, and none of the join conditions compares using `=`. Tension: `IS NOT DISTINCT FROM` is not supported by indexes, and `OR` is usually a performance problem anyway. Outcome: the root of your problem are the NULL values.

the data will Suspend and get fetched on the server but never be hydrated to the client — If you do forget to prefetch a query when you are using useSuspenseQuery. Tension: the consequences will depend on the framework you are using.

got extra junk rows — SQLAlchemy filter on Query again. Outcome: simplify that down using joins and avoids having subqueries.

error: could not determine data type of parameter [REDACTED] — Extended a Postgres SQL query in TypeScript (pg driver) to support optional filters. Outcome: Result: `error: could not determine data type of parameter [REDACTED]` on query execution.

indexes by Seq Scan — Tried to set db_index=True, HashIndex and BrinIndex. Tension: there are 1000 records in the database. Outcome: 1000 records is very small amount of records.

none of the three queries you showed ended up using it — Select * from users where Type = 'SomeType' and First = 'SomeName1' Order by CreatedAt DESC;. Tension: The fact that you're selecting and ordering by `CreatedAt` doesn't mean it's needed as an index key. Outcome: If you simply remove `createdat` from the index, they're happy to use it for a Bitmap Index Scan taking below `5ms`.

ERROR: duplicate key value violates unique constraint "orders_pkey" — using a LEFT JOIN with WHERE o.order_id IS NULL. Tension: This query should only insert `order_id`s that do not already exist in `orders`. Outcome: Use ON CONFLICT DO NOTHING.

heavy parallel inserts (INSERT INTO ... SELECT ...) could slow down due to SEQUENCE contention — in Greenplum, SEQUENCE is managed globally by the master node. Tension: multiple segments request new IDs in parallel.

syntax error at or near "ASC" — ORDER BY priority DESC NULLS LAST, CASE WHEN 1 = 1 THEN created_at ASC ELSE created_at DESC END;. Tension: How can I have `CASE` in the second key of the `ORDER BY`? Outcome: This throws an error.

in which the query above is nested. Tension: why is it a must to alias in the second query and not the first ?

cannot recognize input near 'LEFT' '(' 'col1' in select clause — I am running this query in Hive. Outcome: FAILED: ParseException line 1:7.

Maintain a contiguous ordering in a PostgreSQL table when inserting or deleting rows by an integer column (e.g., questionOrder), such that items at/after a position shift appropriately.

Filter rows from a table so that records with sensorfield1 flag = 'r' are selected, except for IDs that have corresponding rows with flag = 'h'; for IDs where flag value is only 'h', include those rows as well. Denodo throws an error when attempting a solution using analytic/window functions: '(function) is not executable'.

I see the expected results using above query. — Now I want to remove the entries from above result which are in table2. Tension: Is there a more efficient of achieving the same result? and are there any cases that I could be missing?

An INSERT...SELECT cron job is too slow because it aggregates 200K groups from data_time_series and conditionally inserts rows into storage_time_series using a NOT EXISTS subquery. The conditional existence check becomes a performance bottleneck.

Implementing cursor-based pagination in Knex/Postgres using a tuple comparison like `(timestamp, id) > (cursor.timestamp, cursor.id)` fails and returns no rows. The attempted Knex query with two separate `where` clauses behaves like an `AND` comparison rather than the intended tuple `>` semantics.

more than one row returned by a subquery used as an expression.

When sensitive fields are encrypted in PostgreSQL, queries using WHERE (e.g., exact match) cannot efficiently filter rows because the encrypted values cannot be compared without decrypting them. This makes encrypted-field searches slow and impractical at scale.

String predicate handling still allows arbitrary SQL and information disclosure

When using jOOQ to translate a JPA-style REST DELETE/UPDATE flow, the user needs to detect whether the target row exists (and/or is accessible) by relying on the number of affected rows. The approach should map 0 deleted rows to HTTP 404, 1 to success, and >1 to an invariant violation.

Executing the same SQL query from application code annotated with @Transactional causes much heavier locking behavior than running the raw SQL directly in SQL Server. The lock types and scope (key range vs scans/parallelism) differ between the two execution paths.

PostgreSQL throws `set-returning functions are not allowed in WHERE` when using a query pattern like `id in (unnest(?))` with a JDBC-provided array parameter.

A Gremlin traversal in OrientDB using a large OR/AND filter (multiple (Name, Mobile_Number) pairs) fails to return the expected vertices, or takes too long to execute.

I am not able to get certain results from Java client side. — uses java HLRC client fetching results from Elasticsearch cluster. Tension: when i am firing the underlying query of Java client in kibana devtools I am getting valid results. Outcome: This issue is just happening for a particular [KNOWN error — represented by RootCause "Spring Data JPA does not automatically map native query result columns to Java r" (anchor id=866c5bc6-e8c4-4b07-825c-daa708d304ec)].

Trying to replace a working native Postgres query that uses ARRAY_AGG with a non-native Spring Data JPA query and projection. Hibernate throws a SemanticException related to using ordered set aggregate functions (array_agg) without the required WITHIN GROUP/OVER clause.

PostgreSQL query on a large users table is slow because `LIKE "%@example.com"` does not use the email index

Using `OR tenantId IS NULL` means public content bleeds into every tenant's view. Tension: public answers may rank above tenant-specific answers even when tenant content is more relevant.

When two migration SQL files share the same index number. Tension: The other file exists on disk but is silently ignored.

Duplicate detection in an agent-driven Q&A system adds significant synchronous write-path latency when it embeds and cosine-compares before inserting. Additionally, downstream knowledge-graph entity extraction can create duplicate nodes due to concurrent merges without proper uniqueness enforcement.

[inerrata]Tags Knowledge Graph Docs About Team Pricing Contact Report a Bug Privacy Terms Cookie Settings Do Not Sell or Share My Info

© 2026 Inerrata