replaced table-driven TestRunSql w/txtar-based TestSql_RunSql

- TestEscapeSqlName → TestSql_escapeSqlName
- updated sql subcommand in README

Author: zacharysyoung

README.md

@@ -444,14 +444,15 @@ Run SQL queries on CSVs.
 Usage:
 
 ```shell
-gocsv sql --query QUERY FILE [FILES]
+gocsv sql (--query QUERY | --file SQL_SCRIPT ) FILE [FILES]
 ```
 
 Arguments:
 
 - `--query` (shorthand `-q`) The SQL query to run.
+- `--file` (shorthand `-f`) The path to the SQL script to run.
 
-When passing in files, you may read from standard input by specifying the filename `-`.
+When passing in files, you may read one file from standard input by specifying the filename `-`.
 
 Table names are derived from the CSV filenames by taking the base filename without the file extension. For example, `test-files/stats.csv` is referenced as a table with the name `stats`. The table from standard input `-` should be referenced as the table `stdin`.
 
@@ -647,36 +648,36 @@ cat test-files/left-table.csv \
 
 ### Pipelining Support
 
-| Subcommand    |    Input            |  Output  |
-| ------------- | :-----------------: | :------: |
-| add           |  ✔           | ✔ |
-| autoincrement |  ✔           | ✔ |
-| behead        |  ✔           | ✔ |
-| clean         |  ✔           | ✔ |
-| delimiter     |  ✔           | ✔ |
-| describe      |  ✔           |   N/A    |
-| dimensions    |  &#x2714;           | &#x2714;<sup>*</sup> |
-| filter        |  &#x2714;           | &#x2714; |
-| head          |  &#x2714;           | &#x2714; |
-| headers       |  &#x2714;           | &#x2714;<sup>*</sup> |
-| join          |  &#x2714;           | &#x2714; |
-| ncol          |  &#x2714;           |   N/A    |
-| nrow          |  &#x2714;           |   N/A    |
-| rename        |  &#x2714;           | &#x2714; |
-| replace       |  &#x2714;           | &#x2714; |
-| sample        |  &#x2714;           | &#x2714; |
-| select        |  &#x2714;           | &#x2714; |
-| sort          |  &#x2714;           | &#x2714; |
-| split         |  &#x2714;           |   N/A    |
-| sql           |  &#x2714;<sup>&#x2020;</sup>   | &#x2714; |
-| stack         |  &#x2714;<sup>&#x2020;</sup>   | &#x2714; |
-| stats         |  &#x2714;           |   N/A    |
-| tail          |  &#x2714;           | &#x2714; |
-| transpose     |  &#x2714;           | &#x2714; |
-| tsv           |  &#x2714;           | &#x2714; |
-| unique        |  &#x2714;           | &#x2714; |
-| view          |  &#x2714;           |   N/A    |
-| xlsx          |     N/A             | &#x2021; |
+| Subcommand    |            Input            |        Output         |
+| ------------- | :-------------------------: | :-------------------: |
+| add           |          &#x2714;           |       &#x2714;        |
+| autoincrement |          &#x2714;           |       &#x2714;        |
+| behead        |          &#x2714;           |       &#x2714;        |
+| clean         |          &#x2714;           |       &#x2714;        |
+| delimiter     |          &#x2714;           |       &#x2714;        |
+| describe      |          &#x2714;           |          N/A          |
+| dimensions    |          &#x2714;           | &#x2714;<sup>\*</sup> |
+| filter        |          &#x2714;           |       &#x2714;        |
+| head          |          &#x2714;           |       &#x2714;        |
+| headers       |          &#x2714;           | &#x2714;<sup>\*</sup> |
+| join          |          &#x2714;           |       &#x2714;        |
+| ncol          |          &#x2714;           |          N/A          |
+| nrow          |          &#x2714;           |          N/A          |
+| rename        |          &#x2714;           |       &#x2714;        |
+| replace       |          &#x2714;           |       &#x2714;        |
+| sample        |          &#x2714;           |       &#x2714;        |
+| select        |          &#x2714;           |       &#x2714;        |
+| sort          |          &#x2714;           |       &#x2714;        |
+| split         |          &#x2714;           |          N/A          |
+| sql           | &#x2714;<sup>&#x2020;</sup> |       &#x2714;        |
+| stack         | &#x2714;<sup>&#x2020;</sup> |       &#x2714;        |
+| stats         |          &#x2714;           |          N/A          |
+| tail          |          &#x2714;           |       &#x2714;        |
+| transpose     |          &#x2714;           |       &#x2714;        |
+| tsv           |          &#x2714;           |       &#x2714;        |
+| unique        |          &#x2714;           |       &#x2714;        |
+| view          |          &#x2714;           |          N/A          |
+| xlsx          |             N/A             |       &#x2021;        |
 
 \* `dimensions` and `headers` write to CSV format when using the `--csv` argument.