“PSQL” Réponses codées

postgres

SELECT column_name(s)
FROM table_name
WHERE column_name IN (value1, value2, ...); 
Delightful Dragonfly

Postgresql

# The bash function below utilizes the CLI tool psql to vacuum analyze tables
# in a single schema which can be identified by either passing the name of
# the schema as the first parameter to the function
# or setting the environment variable PG_SCHEMA:
#

vacuum_analyze_schema() {
    # vacuum analyze only the tables in the specified schema

    # postgres info can be supplied by either passing it as parameters to this
    # function, setting environment variables or a combination of the two
    local pg_schema="${1:-${PG_SCHEMA}}"
    local pg_db="${2:-${PG_DB}}"
    local pg_user="${3:-${PG_USER}}"
    local pg_host="${4:-${PG_HOST}}"

    echo "Vacuuming schema \`${pg_schema}\`:"

    # extract schema table names from psql output and put them in a bash array
    local psql_tbls="\dt ${pg_schema}.*"
    local sed_str="s/${pg_schema}\s+\|\s+(\w+)\s+\|.*/\1/p"
    local table_names=$( echo "${psql_tbls}" | psql -d "${pg_db}" -U "${pg_user}" -h "${pg_host}"  | sed -nr "${sed_str}" )
    local tables_array=( $( echo "${table_names}" | tr '\n' ' ' ) )

    # loop through the table names creating and executing a vacuum
    # command for each one
    for t in "${tables_array[@]}"; do
        echo "doing table \`${t}\`..."
        psql -d "${pg_db}" -U "${pg_user}" -h "${pg_host}" \
            -c "VACUUM (ANALYZE) ${pg_schema}.${t};"
    done
}
LinuxMalaysia

postgresql

sudo mkdir -p /etc/paths.d &&
echo /Applications/Postgres.app/Contents/Versions/latest/bin | sudo tee /etc/paths.d/postgresapp
Clean Caterpillar

PSQL

In PostgreSQL the system determines which table is meant by following a search path, which is a list of schemas to look in.

The first matching table in the search path is taken to be the one wanted, otherwise, if there is no match a error is raised, even if matching table names exist in other schemas in the database.

To show the current search path you can use the following command:

SHOW search_path;
And to put the new schema in the path, you could use:

SET search_path TO myschema;
Or if you want multiple schemas:

SET search_path TO myschema, public;
Reference: https://www.postgresql.org/docs/current/static/ddl-schemas.html
Alive Anaconda

postgres

# Use postgres/example user/password credentials
version: '3.1'

services:

  db:
    image: postgres
    restart: always
    environment:
      POSTGRES_PASSWORD: example

  adminer:
    image: adminer
    restart: always
    ports:
      - 8080:8080
Uninterested Unicorn

postgresql

CREATE OR REPLACE FUNCTION foo()
RETURNS void AS $$
BEGIN
  RAISE NOTICE 'Hello from void function';
END;
$$ LANGUAGE plpgsql;

-- direct call from SQL
SELECT foo();

-- in PLpgSQL
DO $$
BEGIN
  SELECT foo(); -- is not allowed
  PERFORM foo(); -- is ok
END;
$$;
Noemi Rosario Ancari Villcarani

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