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Load when hitting DuckDB syntax errors or writing DuckDB-specific SQL. Covers gotchas that differ from PostgreSQL/MySQL.
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Based on SOC occupation classification
| name | duckdb-sql |
| description | Load when hitting DuckDB syntax errors or writing DuckDB-specific SQL. Covers gotchas that differ from PostgreSQL/MySQL. |
| type | skill |
5/2 = 2. Fix: CAST(numerator AS DOUBLE) / denominatorCAST(DATE_TRUNC('month', col) AS DATE)INTERVAL '1' DAY (quoted), NOT INTERVAL 1 DAYcol + INTERVAL '1' DAY and DATE_DIFF('day', start, end)COALESCE(SUM(col), 0) if 0 is needed.decimal(6,2),
cast the FINAL output to match: CAST(ROUND(AVG(col), 2) AS DECIMAL(6,2)).
Do NOT cast the input — cast the result after rounding.(SELECT MAX(date_col) FROM source) to anchor to the data's actual date rangeSTRPTIME(col, '%d/%m/%Y')::DATETRY_STRPTIME returns NULL on failure (safe)CAST(date_str AS DATE) on non-ISO stringsFilter window function results without a subquery:
SELECT *, ROW_NUMBER() OVER (PARTITION BY group ORDER BY col DESC) AS rn
FROM table
QUALIFY rn <= 10
SELECT UNNEST(GENERATE_SERIES(min_date::DATE, max_date::DATE, INTERVAL '1' DAY)) AS date_day
Always use the primary fact table's max date as endpoint — call get_date_boundaries first.
CAST(x AS INTEGER), CAST(x AS DOUBLE), CAST(x AS VARCHAR), CAST(x AS DATE)
TRY_CAST returns NULL on failure.
Load when working with Xata Postgres branches: forking a branch, building or testing dbt models on a branch, wiring dbt to a branch's credentials, diffing two branches, or the pre-merge impact report. Covers create_xata_branch, delete_xata_branch, get_dbt_profile, xata_branch_diff, schema_diff_branches, and pgroll migrations.
Load at Step 1 before exploring the project. Covers output shape inference, incremental model handling, and what to trust in YML.
Use this skill before writing any SQL query. Covers: output shape inference (cardinality clues from the question), efficient schema exploration, iterative CTE-based query building, structured verification loop (row count, NULL audit, fan-out check, sample inspection), error recovery protocol, saving output to result.sql and result.csv, turn budget management, and common benchmark traps.
Populate the knowledge base from dbt project research. Proposes entries across all 6 categories at org, project, and connection scopes.
Load FIRST before any dbt project work. Covers the full 8-step dbt workflow: project scanning, skill loading, validation, macro discovery, research, technical spec, SQL writing, and verification. Also covers output shape inference, incremental model handling, and what to trust in YML.
Loaded at Step 2 for the full workflow. Covers column naming, type preservation, JOIN defaults, lookup joins, sibling models, materialization, packages, and filtering rules.