Exasol Database Skill

Trigger when the user asks for Exasol database interaction, exapump, Exasol SQL, EXA_ system views, schemas, tables, or query execution outside exasol-import and exasol-export.

Step 0: Establish Connection

Ensure a working exapump profile before proceeding:

1. If the user names a profile, test it with exapump sql --profile <name> "SELECT 1"; always place --profile after the subcommand. Otherwise test the default profile with exapump sql "SELECT 1".
2. On success, proceed — and keep the same --profile <name> after the subcommand on every later exapump command.
3. On failure, run exapump profile list to see which profiles exist.
4. If profiles exist, present them and ask which to use, then inspect that one with exapump profile show <name> — it masks credentials — to confirm the required fields are set. Never read, cat, or print ~/.exapump/config.toml; it stores credentials in clear text. If a credential value does appear in any command output, do not repeat it in the conversation.
5. If no usable profile exists, have the user create one locally with exapump profile add <name> (omit --password and exapump prompts on a hidden line) or exapump profile init, then retry step 1. Never ask the user to paste a password into the conversation, and never pass one as a command-line argument.

Routing Algorithm

After the connection is established, determine the task type and load only the references needed:

1. SQL execution (queries, DDL, DML, schema inspection):

   • Load: references/exapump-reference.md (CLI usage)
   • Load: references/exasol-sql.md (core SQL behavior)
   • Load: references/exasol-grammar.md for the exact statement syntax (SELECT/DQL, DDL, DML, DCL, session & admin) — the EBNF the docs.exasol.com syntax diagrams are generated from. Consult it before inventing syntax or when unsure a clause exists. Read only the section you need — it is large.
   • Load: references/exasol-grammar-functions.md for built-in function, operator, predicate, literal, and data-type syntax (e.g. the exact argument order of a function). Same EBNF source, split out so statement lookups don't pull in the full function catalog.
   • Load: references/exasol-reserved-keywords.md and ingest the full list before designing queries — every reserved word (pinned to Exasol 2026.1.0) must be double-quoted when used as an identifier. On a keyword-related syntax error, re-query the running DB as described in Before writing any SQL in case the file has drifted from the DB version.

2. Table design (DISTRIBUTE BY, PARTITION BY, CREATE TABLE layout):

   • Load: references/table-design.md

3. Query profiling / performance (slow queries, data skew, REORGANIZE):

   • Load: references/query-profiling.md

4. Analytics / window functions (ROW_NUMBER, RANK, LAG/LEAD, QUALIFY, GROUPING SETS):

   • Load: references/analytics-qualify.md
   • Load: references/exasol-grammar-functions.md for exact analytic-function and OVER (…) window-clause syntax

5. BucketFS file management (upload/download/list/delete files in BucketFS, bfsdefault, bucket paths):

   • Activate the exasol-bucketfs skill for guidance

6. UDF development (CREATE SCRIPT, ExaIterator, SCALAR/SET, Script Language Containers, SLC, exaslct):

   • Activate the exasol-udfs skill for guidance

Multiple routes can apply — load all that match.

7. Before writing any SQL (applies to routes 1–4):
   • Ingest references/exasol-reserved-keywords.md before designing queries — load the reserved-word list (pinned to Exasol 2026.1.0) up front so you quote reserved identifiers from the start rather than discovering them through errors
   • Always double-quote every identifier (column names, table names, schema names) in SELECT, FROM, WHERE, GROUP BY, ORDER BY, and JOIN clauses — without exception
   • This preserves mixed-case names and prevents reserved-keyword errors in a single rule
   • Do NOT quote SQL keywords, functions, or aliases — only object identifiers
   • If a query fails with a syntax error that looks like an unquoted reserved word, do not trust the pinned file blindly — the DB may be newer or older than 2026.1.0 and the list can drift either way. Fetch the authoritative list for the running version and reconcile: exapump sql "SELECT KEYWORD FROM EXA_SQL_KEYWORDS WHERE RESERVED ORDER BY KEYWORD"
   • For the exact shape of any clause (optional parts, ordering, comma-lists), consult references/exasol-grammar.md (statements) or references/exasol-grammar-functions.md (functions / predicates / literals / data types) rather than guessing from examples.

Related Skills

This skill handles core database interaction: connecting, SQL execution, schema inspection, and table design. For direct native IMPORT and local file movement into Exasol, use exasol-import. For direct native EXPORT and local file movement out of Exasol, use exasol-export. For broad extension, connector, or federation selection, use exasol-extension-catalog. For BucketFS file management (upload, download, list, delete), the exasol-bucketfs skill provides specialized guidance and will activate automatically when relevant. For UDF development and Script Language Containers, the exasol-udfs skill provides specialized guidance and will activate automatically when relevant.